volume I
 summary
          ANALYSIS OF
          AND COSTS
             Of
          RETROFIT EMISSION
          CONTROL SYSTEMS
             for
          USED MOTOR
          Environmental Protection Agency
                                MAY 1972

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volume I
 summary
            ANALYSIS OF
            AND COSTS
                of
            RETROFIT EMISSION
            CONTROL SYSTEMS
                for
            USED MOTOR
            VEHICLES
            prepared under
            EPA Contract 68-04-0038

            by
            Olson Laboratories, Inc.
            500 East Orangethorpe Avenue
            Anaheim, California 92801
            In Association With Northrop Corporation

            Report 71Y233
            MAY 1972
            for
            ENVIRONMENTAL PROTECTION AGENCY
            Office of Air Programs
            Division of Emission Control Technology
            2565 Plymouth Road
            Ann Arbor, Michigan 48105

                                   Approved by:
                                             D. D. Foulds
                                             Vice President
                                             Olson Laboratories, Inc.

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                                     FOREWORD
The Environmental Protection Agency,  as Administrator of the Clean Air Amendments
Act of 1970, is required to assist States and air pollution control agencies in
meeting national ambient air quality standards and mobile or stationary source
emission standards, by issuing information on control techniques.   Contract
68-04-0038 was performed with the Office of Air Programs, Division of Emission Con-
trol Technology, to determine what emission control techniques are feasible for
retrofit to used cars, considering emission reduction effectiveness, costs, effect
on vehicle performance, and the facilities and labor skills required for retrofit
device installation and eventual maintenance and inspection.  This report documents
the results obtained, the pertinent data upon which the results are based, the
techniques of test and analysis, and the recommendations for future programs
to implement the results.  The report consists of the following six volumes:

     I.    Program Summary:  Highlights the principal program results and
           conclusions as to the overall feasibility of retrofit methods for
          .vehicle emission control.   Provides guidelines for the evaluation of
           retrofit approaches and the implementation of control programs.

     II.   System Descriptions:  Documents the physical, functional, and
           performance characteristics of the candidate retrofit methods and
           their installation requirements and costs.

     III.  Performance Analysis:  Documents the relative effectiveness and costs
           of retrofit methods, the techniques of analysis and testing, and the
           assumptions and rationale upon which the analysis was based.

     IV.   Test and Analytical Procedures:  Documents the approach to the overall
           program objectives and the tasks and procedures implemented to meet
           the objectives.

     V.    Appendices:  Documents the raw data obtained from retrofit development
           sources and data of overall applicability to the report.

     VI.   Addendum for Durability Tests:  Documents the results of 25,000-mile
           durability tests on four representative retrofit devices.
                                       iii

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                                      ABSTRACT
 The purpose  of  this  EPA-contracted  program was  to  examine  the  effectiveness and
 costs  of retrofit  methods  for  control  of  emissions  from  gasoline-powered,  light-duty
 used automobiles.  This  six-volume  report  provides  the results of an extensive eval-
 uation of current  retrofit  technology  to  States and agencies which have  to establish
 or  evaluate  automotive emission  control programs.   It also provides detailed guide-
 lines  and  an evaluation methodology  to assist in the development of specific air
 pollution control  programs  or  abatement strategies  using retrofit devices as they
 apply  to used car  emission  control requirements.  The report presents a  summary of
 all  known retrofit emission control  techniques for  used cars in terms of emission
 reduction effectiveness, costs,  effect on  the vehicle's performance, and the facili-
 ties and labor  skill needed for  device installation, maintenance, and inspection.

 The  term "retrofit method"  as used in this program  is defined as "any device or
 system  that may be added to a car and/or any modification or adjustment, beyond that
 of regular vehicle maintenance, which may be made to vehicles to reduce their emis-
 sions. "(1)  Regular vehicle maintenance,  engine tuneup,  the General Motors, Ford,
 and Chrysler used car retrofit systems, as well as vehicle inspection programs, were
 specifically excluded from  study.  Other programs have studied, or are currently
 studying,  these alternate approaches.

A thorough search was made  for all sources of information on all known retrofit
methods, developers,  and producers.  Input data from the participating developers
 and producers were used in  the evaluation process and to categorize the principles
 of retrofit device operation.   Generic groups of:  (1) exhaust emission control, (2)
 crankcase blowby control, (3)  evaporative emission control, and (4) combinations
were evaluated.   The study  emphasis, however, was placed on exhaust emission control
approaches.

Several  representative devices were actually tested to provide exhaust emissions,
 fuel consumption, and driveability performance data which are considered to be typ-
 ical for the existing used car population.  The test program was performed on used
cars without factory installed exhaust control systems.

Concurrent with the test program an engineering analysis was conducted on each
retrofit system to document technical characteristics, costs, and effects on vehicle
performance.   The data obtained,  both from the retrofit  tests and the engineering
analysis, were then processed  through an  evaluation methodology especially developed
    Environmental Protection Agency Contract 68-04-0038, Analysis of Effectiveness
    and Costs of Retrofit Emission Control Systems for Used Vehicles, 30 June 1971

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to analyze the principal performance parameters of the different retrofit systems.
The methodology developed is applicable to the evaluation of any exhaust emission
control method, whether for cars that may or may not already be equipped with other
emission control systems.

The study showed that a large number of retrofit methods and prototype devices are
available for the majority of the used car population.  Most can be readily mass
produced and marketed if the necessary economic incentives arise.  They cover a wide
spectrum of effectiveness and cost.  Those devices which are most effective in reduc-
ing emissions are also generally the most expensive.  The study indicated that cer-
tain of these retrofit devices are technically feasible, but that careful tradeoffs
may be required between emission reduction effectiveness and costs to achieve an
optimum solution to the air quality control requirements of different regions.

The problem of durability (device performance versus mileage accumulation) was also
investigated in the program.  The evaluation of the durability test results is being
completed and will be covered in Volume VI, which is to be published shortly.
                                        vi

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                                  ACKNOWLEDGMENTS
This program was conducted under the direction and with the assistance  of  Dr.  Jose
L. Bascunana, Project Officer of the Environmental Protection Agency.   Emission
Control Technology, Inc., provided the methodology for performance analysis  under
a subcontract agreement with Olson Laboratories,  Inc.

The accomplishment of this program was made possible by the cooperation and
assistance of the many developers and manufacturers of retrofit devices.  Their
contribution of coordination time, data, and retrofit  device hardware  is very
much appreciated.
                                         vii

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                   GLOSSARY

AMA       Automobile Manufacturers Association
CEI       Cost Effectiveness Index
CI        Cost Index
CID       Cubic inch displacement
CNG       Compressed natural gas
CO        Carbon monoxide
CVS       Constant volume sampling
DI        Driveability Index
EGR       Exhaust gas recirculation
El        Emission Index
EPA       Environmental Protection Agency
gm/mi     Grams per mile
HC        Hydrocarbons
LNG       Liquefied natural gas
LPG       Liquefied petroleum gas
MMBM      Mean-miles-before-maintenance
MMBPF     Mean-miles-before-partial-failure
MMBTF     Mean-miles-before-total-failure
mph       Miles per hour
mpg       Miles per gallon
MTTM      Mean-time-to-maintain
MTTR      Mean-time-to-repair
NDIR      Nondispersive infrared
NOx       Oxides of nitrogen
OEM       Original equipment
PCV       Positive crankcase ventilation
PI        Performance Index
ppm       Parts per million
SAE       Society of Automotive Engineers
WOT       Wide open throttle
                     viii

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                                CONTENTS  (CONTINUED


Table                                                                           Page

 4-3      Average Percentage Exhaust Emission Reduction of Devices Evalu-
            ated in Retrofit Program - Listed by Device Classification .  .  .      4-8
 4-4      Percentage Exhaust Emission Reduction of Devices Tested in
            Retrofit Program 	     4-12
 4-5      Mean Percentage Emission Reduction and 90 Percent Confidence
            Intervals for Exhaust Emission Control Retrofit Systems Tested
            at Anaheim, California and Taylor, Michigan  . .	     4-15
 4-6      Driveability and Safety Characteristics for Devices Tested in
            Retrofit Program 	     4-20
 4-7      Reliability and Corrective Maintenance Estimates of Devices
            Evaluated in Retrofit Program  	     4-24
 4-8      Preventive Maintenance Estimates of Devices Evaluated in
            Retrofit Program 	     4-28
 4-9      Initial and Recurring Costs of Devices Evaluated in Retrofit
            Program	     4-37
 4-10     Installation and Skill Level Requirements Summary  	     4-39
 5-1      Performance Summary of Devices Evaluated in Retrofit Program .  .  .      5-2
 6-1      Light-Duty Vehicle Population and Type of Emission Control ....      6-2
 6-2      Development Status and Applicability of Devices Evaluated in
            Retrofit Program 	      6-6
                                         XI

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                                      CONTENTS
Section                                                                         Page

          FOREWORD	      iii
          ABSTRACT 	       v
          ACKNOWLEDGMENTS	      vii
          GLOSSARY	     viii

   1      SUMMARY OF RESULTS AND CONCLUSIONS 	      1-1

          1.1   Fundamental Results and Conclusions   	      1-1
          1.2   Retrofit Device Classification and Descriptions   	      1-4
          1.3   Retrofit Device Performance  	      1-9
          1.4   Evaluation Methodology 	     1-15
          1.5   Development Status and Applicability 	     1-15
          1.6   Guidelines for Selecting and Implementing Feasible
                  Retrofit Methods	     1-17
          1.7   Recommendations	     1-18

   2      RETROFIT PROGRAM APPROACH  	      2-1

          2.1   Retrofit Method Survey 	      2-1
          2.2   Retrofit Method Screening Evaluation 	      2-2
          2.3   Engineering Analysis 	      2-3
          "2.4   Test Program	      2-4
          2.5   Performance Analysis 	      2-6

   3      EVALUATION METHODOLOGY 	 	      3-1

          3.1   Criteria Index	      3-1
          3.2   Performance Index  	      3-2
          3.3   Cost Effectiveness Index	      3-3
          3.4   Sensitivity Analysis 	      3-4

   4      RETROFIT DEVICE EVALUATIONS	  .      4-1

          4.1   Emission Reduction 	      4-1
          4.2   Driveability and Safety	     4-18
          4.3   Reliability and Maintainability  	     4-22
          4.4   Initial and Recurring Costs  	     4-35
          4.5   Installation and Skill Level Requirements	     4-36

   5      PERFORMANCE ANALYSIS 	      5-1

          5.1   Criteria Index	      5-1
          5.2   Performance Index  	      5-3
          5.3   Cost Effective Index	      5-4
          5.4   Feasibility	      5-5

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                                CONTENTS  (CONTINUED)


 Section                                                                        Page

    6      RETROFIT DEVICE DEVELOPMENT STATUS AND VEHICLE APPLICABILITY ...     6-1

          6.1   Vehicle Applicability of Retrofit Devices  	     6-1
          6.2   Retrofit Device Development Status and Applicability
                  Summary	     6-5

    7      GUIDELINES FOR SELECTING AND IMPLEMENTING RETROFIT METHODS .....     7-1

          7.1   Defining the Required Emission Reduction 	 .     7-1
          7.2   Defining the Retrofit Vehicle Population 	     7-2
          7.3   Identifying Candidate Retrofit Methods 	     7-2
          7.4   Determining Cost Effective Retrofit Methods  	     7-2
          7.5   Defining the Certification Program 	     7-3
          7.6   Cost Effectiveness Studies of Alternative Programs 	     7-3
          7.7   Preparing an Implementation Plan	     7-3
          7.8   Implementing the Plan	     7-3

Append ix

   A      Sample Performance Evaluation Methodology Calculation  ......     A-l

   B      Retrofit System Description Index  	     B-l

   C      Tables of Contents for Volumes II, III,  IV, V,  and VI	     C-l
Figure

  1-1

  4-1
                                   ILLUSTRATIONS
Pooled Mean Exhaust Emission Reduction of Devices Tested in the
  Retrofit Program	
Percentage Exhaust Emission Reduction Means and 90% Confidence
  Limits for Exhaust Emission Control Retrofit Systems Tested at
  Anaheim, California, and Taylor, Michigan  	 .....
                                                                      Page
1-11
                                                                                4-16
                                       TABLES
Table

 1-1
 1-2
 2-1
 4-1
 4-2
Classification of Retrofit Methods . 	 .,
Performance Parameters and Evaluation Criteria 	 ,
Retrofit System Types Tested in Retrofit Program .  	
Devices Evaluated in the Retrofit Program  	
Average Percentage Exhaust Emission Reduction by Test Procedure
  for Devices Evaluated in Retrofit Program  	 . . . .
Page

 1-5
1-16
 2-3
 4-2

 4-6
                                          x

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SUMMARY OF RESULTS
AND CONCLUSIONS

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                                     SECTION 1

                         SUMMARY OF RESULTS  AND CONCLUSIONS
1.1  FUNDAMENTAL RESULTS AND CONCLUSIONS

The fundamental results and conclusions of the  study  of  retrofit method effectiveness
and costs are summarized as follows:

     «    Retrofit Emission Reductions and Costs  -  Retrofit  devices which are
          designed to control emissions from gasoline-powered  light duty
          vehicles can be classified  according  to the following sources of
          vehicle emissions they control:

              a.  Crankcase Blowby Emission Control Systems

              b.  Fuel Evaporative Emission Control Systems
              c.  Exhaust Gas Emission Control  Systems

          It has been estimated that  reliable crankcase  blowby control systems
          can reduce up to 20 percent of all the  hydrocarbons  emitted by cars
          without any emission controls.  Twenty-three percent of  the current
          national car population do  not have controls for crankcase emissions.
          Feasible retrofit crankcase blowby control  systems are currently
          available.  The conventional types cost up  to  $40  installed.

          It has also been estimated  that  reliable  evaporative control devices
          could reduce all the hydrocarbons emitted from an  uncontrolled car
          as much as 20 percent.  About 85 percent  of the current  total car
          population do not have evaporative controls.  There  were no retrofit
          fuel evaporative emission control devices for  used vehicles at the
          time of this study.  However, on the  basis  of  the  systems being
          supplied on new vehicles, it was estimated  that a  used car retrofit
          evaporative control could cost as much  as $140.

          Exhaust gas emissions account for about 60  percent of the hydrocarbon
          emissions, essentially 100  percent of the carbon monoxide, and 100
          percent of the oxides of nitrogen from  an uncontrolled vehicle.

          A group of 11 retrofit exhaust devices  was  selected  for  testing in
          the retrofit program.  Four of these  devices received up to 18 tests.
          The emission reductions with 90  percent confidence limits of the mean
          reduction for these four representative retrofit exhaust emission
          control systems are presented in the  following table:
                                         1-1

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DEVICE NUMBER
AND
DESCRIPTION

Manifold
96 Catalytic Converter with
Distributor Vacuum
Advance Disconnect
175 Ignition Timing Modifica-
tion with Lean Idle
Adjustment
246 Speed-Controlled Exhaust
Gas Recirculation with
Distributor Vacuum
Advance Disconnect
PERCENT EXHAUST EMISSION REDUCTIONS (1)
HC
Pooled
Mean
.Reduction
21
68
19
12
90% Confidence
Limits of the
Mean Reduction
10 to 32
53 to 90
9 to 29
3 to 21
CO
Pooled
Mean
Reduction
58
63
46
31
90% Confidence
Limits of the
Mean Reduction
22 to 80
37 to 97
-8 to 77
6 to 60
NOx
Pooled
Mean
Reduction
-5
48
37
48
9CK Confidence
Limits of the
Mean Reduction
-15 to 5
17 to 64
27 to 47
43 to 52
(1) Exhaust tests conducted by the 1972 Federal Test Procedure.
Retrofit emission control systems include initial installation costs and
recurring costs to operate and maintain the device.  Additional costs for
engine tuneup prior to device installation must also be considered if this
procedure is specified as part of the installation.  The costs for engine
tuneup were excluded in the scope of this study, except for those tuneup
related parts and/or adjustments required by the retrofit device installa-
tion.  The study indicated that those retrofit control systems which are
most effective generally cost more money to install and maintain.  However,
the question of reasonable costs for retrofit systems ultimately depends
on the emission reduction objectives of State or air pollution control
agencies, and the options which may be available to meet those objectives.

Typical costs of retrofit systems tested in the program ranged from $21 to
$175.  The catalyst system evaluated in the retrofit program reportedly
has an initial cost of $175 when installed with an air pump on an 8-cylin-
der vehicle.  The ignition timing modification system and the exhaust gas
recirculation system have initial costs of $45 and $89, respectively.  The
air bleed system which received 18 tests costs between $56 and $64.  An-
other air bleed system evaluated reportedly costs about $23.  These prices
are estimates for prototype systems based on information provided by the
retrofit developers.

Recurring costs are significantly influenced by the change in gasoline
mileage as a result of a retrofit system installation.  Fuel consumption
measurements were conducted while using the 1972 Federal Exhaust Emissions
Test Procedure (which covers typical urban driving and speeds up to 57 mph).
Average penalties in fuel consumption as high as 10 percent (less miles per
gallon) and improvement as high as 7 percent (more miles per gallon) were
measured during these tests for some of the devices which received up to 18
tests.   Additional testing must be undertaken to determine fuel consumption
for freeway driving and to establish the statistical significance of the data.

Catalyst systems require lead free fuels to maintain satisfactory effective-
ness over service periods of 25,000 miles.   The other types of systems
tested  in the retrofit program did not require special fuels.
                               1-2

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 In  addition  to  the  fuel costs, maintenance of a retrofit device adds to
 the recurring costs.  Typical maintenance for air bleed systems requires
 air filters  to  be changed every 12,000 miles.  Exhaust gas recirculation
 systems require cleaning, of the control valve every 6,000 miles.  Catalyst
 systems require a change of catalyst at 25,000-mile intervals.  Electronic
 ignition modification systems require no maintenance, in general, and in
 most  cases  their  repair is not possible;  in  the event such devices  fail,
 replacement  with  a  new unit is required.

 Driveability and  Safety - In general, the devices that received driveabil-
 ity tests in the  retrofit study appeared to  degrade vehicle driveability;
 however, driveability was still acceptable.  Average acceleration times at
 wide  open throttle  were about 5 to 10 percent slower.  High altitude (6,000-
 8,000  ft) did not affect the operation of the vehicle with the retrofit in-
 stalled any  differently than the driveability tests conducted near sea level.

 In general there were no gross safety problems due to retrofit installation.
 Some  of the  devices appeared to have potential safety hazards, but it is
 believed these  could be eliminated by redesign.

 Reliability  - Reliability in mean-miles-before-partial and total failure
 was estimated to  be 50,000 service miles or  more for all devices for
 which  sufficient  data could be obtained or developed.

 Installation. Inspection and Skill Level Requirements - Although the devices
 evaluated did not require special tools for  installation, practically all
 require special equipment for low emission adjustment.  In most cases,  the
 retrofit developer  specified that the engine be well tuned prior to device
 installation.   To ensure low emissions, an HC and CO meter would be required
 for effective retrofit device and related tuneup adjustments.  The install-
 ation  of the devices requires normal automotive mechanical skills.  However,
 most auto mechanics are not presently capable of properly adjusting a retrofit
 device and related  engine tuneup parameters  for low emissions without some
 additional training.  Technician upgrading through training programs would be
 required for a  successful  and effective retrofit program.

 Retrofit Device Vehicle Applicability - The  retrofit systems evaluated in
 this study are  applicable to most pre-1968 domestic model vehicles (pre-1966
 for California) not originally equipped with exhaust controls.  Catalyst
 systems appear  to be applicable as retrofits for additional emission
 reductions on 1968 and later model vehicles.   Distributor vacuum advance
 and exhaust  gas recirculation systems may also be applicable for NOx control
 of these later model-year vehicles.   Air bleed systems can be easily installed
 on vehicles already equipped for HC and CO control,  but consideration must be
 given  to the possibility of over-leaning the carburetor mixture, since these
vehicles already have relatively lean carburetor mixtures.  Foreign car
 retrofit devices were generally not available for analysis during the program;
 however, two retrofit devices  were tested on a small foreign car.

Feasibility Conclusions -  The  study of retrofit method effectiveness and
 costs performed under EPA Contract 68-04-0038 indicated that certain exhaust
 emission control systems  are technically feasible for retrofitting used cars.
The major consideration is one of cost.   In general,  the amount of money spent
 for a device determines the emission reduction effectiveness to be gained.
                                  1-3

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     Some of the main problems likely to be encountered with the retrofit approach
     may not be attributable to the devices.   The vehicles themselves have to be
     in good running condition and well tuned if retrofit devices are to be effec-
     tive.  Vehicle engine defects and malfunctions may degrade device performance,
     and even cause device failure.  Thus, the use of retrofit devices presupposes
     good vehicle condition prior to device installation and good continued
     maintenance.

     Additional results, related to the durability of retrofit devices, will be
     presented in Volume VI.

1.2  RETROFIT DEVICE CLASSIFICATION AND DESCRIPTIONS

Retrofit devices which are designed to control emissions from gasoline-powered
motor vehicles can be classified according to the sources of vehicle emissions they
control:

     Group 1:  Exhaust Emission Control Systems

     Group 2:  Crankcase Blowby Emission Control Systems

     Group 3:  Fuel Evaporative Emission Control Systems

     Group 4:  Combinations of these groups

Table 1-1 shows the detailed classification structure used to categorize retrofit
devices studied in this program.

Exhaust gas accounts for about 60 percent of the hydrocarbon (HC) emissions and
essentially 100 percent of the carbon monoxide (CO) and oxides of nitrogen (NOx)
from an uncontrolled vehicle.  Crankcase blowby accounts for about 20 percent of
the HC emissions, and evaporative emissions from the fuel tank and carburetor
vents account for the remaining 20 percent of the HC emissions.  Control of the
pollutants from these three sources requires devices or methods of varying com-
plexity and, correspondingly, the effectiveness of retrofit devices can vary over
a wide range.  Furthermore, the addition of a retrofit control device to a used
car normally cannot be expected to be as cost effective for control of emissions
as the inclusion of control methods at the time of vehicle manufacture.

 1.2.1  Exhaust Emission Control Systems

In considering the control of exhaust emissions, retrofit devices may be designed
to either work on the exhaust gases after they leave the combustion chambers and
enter into the exhaust system, or they may be designed to decrease the emission
formation by modifications to the induction system and/or the ignition and com-
bustion processes.  Within these two broad categories there were several approaches
which were represented by the devices evaluated in this program.

The three automotive exhaust pollutants currently controlled by law for new light-
duty vehicles (6,000 pounds or less) are hydrocarbons (HC), carbon monoxide (CO)
and oxides of nitrogen (NOx).  Smoke emissions (or particulate matter) are control-
led in some States by local ordinance, but not presently by Federal requirements.
The combination of HC and NOx in the atmosphere plus sunlight causes photochemical
reactions to occur.  This, in turn, forms the reactive compounds which constitute
                                         1-4

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smog.  Carbon monoxide does not enter into the smog reaction, but in itself is a
poisonous gas.

Modification of engine operating parameters, including idle speed, air-fuel ratio
and spark timing, can affect the concentration of these exhaust gas pollutants
from uncontrolled engines.  The objective of applying these modifications is to
optimize the engine operation with respect to exhaust pollutant emissions.  In some
cases, those modifications which reduce HC and CO emissions tend to increase  .
NOx emissions.  When air-fuel ratios exceed about 15-16 to 1, NOx formation
normally decreases with additional mixture leaning.  When adjustments are made
which optimize engine characteristics with respect to low emissions, vehicle drive-
ability performance parameters,  such as acceleration, may be degraded.

                Table  1-1.   CLASSIFICATION  OF  RETROFIT METHODS
    GROUP
TYPE
SUBTYPE
                                                         TITLE
                 1.1
                 1.2
                 1.3
                 1.4
                 2.1
                 2.2
                3.1
                3.2
            1.1.1
            1.1.2
            1.1.3
            1.1.4
            1.1.5

            1.2.1
            1.2.2
            1.2.3
            1.2.4
            1.2.5
            1.2.6

            1.3.1
            1.3.2

            1.4.1
            1.4.2
            1.4.3
              EXHAUST EMISSION CONTROL SYSTEMS
            Exhaust Gas Control Systems
              Catalytic Converter
              Thermal Reactor
              Exhaust Gas Afterburner
              Exhaust Gas Filter
              Exhaust Gas Backpressure
            Induction Control Systems
              Air Bleed to Intake Manifold
              Exhaust Gas Recirculation
              Intake Manifold Modification
              Carburetor Modification
              Turbocharger
              Fuel Injection
            Ignition Control Systems
              Ignition Timing Modification
              Ignition Spark Modification
            Fuel Modification
              Alternative Fuel Conversion
              Fuel Additive
              Fuel Conditioner

              CRANKCASE EMISSION CONTROL SYSTEMS
            Closed System
            Open System

              EVAPORATIVE EMISSION CONTROL SYSTEMS
            Crankcase Storage
            Canister Storage

              EMISSION CONTROL COMBINATIONS
                                        1-5

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 1.2.1.1   Exhaust  Gas  Control  Systems

 One  approach  for  reducing HC  and  CO is  to  subject  the exhaust gas  to an oxidation
 process.  Among the retrofit  devices  studied,  this was  done by using either a  cata-
 lytic  converter,  a thermal  reactor, or  an  afterburner.

 In the catalytic  converter  approach (Device 96), the exhaust gas is passed through
 a catalytic bed for oxidizing HC  and  CO to carbon  dioxide  (C02) and water.(1)  The
 catalyst  is not consumed in the oxidation  reaction, but deterioration may result
 from use  of fuels poisonous to the catalyst (such as leaded gasoline).  The heat
 required  to initiate  oxidation comes  from  the  exhaust gas  itself.  The oxygen  needed
 for  oxidation  in  the  catalytic converter is provided either by leaning the fuel mix-
 ture at the carburetor or by  the  addition  of air into the  exhaust  system.

 The  thermal reactor works in  much the same way.  In the case of the rich mixture
 reactor (Device 244), oxidation occurs  as  a result of air  being pumped directly into
 the  exhaust manifold  near the exhaust valves.  At  that  location the exhaust gas tem-
 perature  is usually high enough to support oxidation of HC and CO  without having to
 use  a  catalyst, if there is enough oxygen  available.  With the lean reactor (Device
 468),  additional air  is not required, since the carburetor is set  at an air-fuel
 mixture ratio which provides  the  required  oxygen.

 The  exhaust gas afterburner (Device 308) also  requires a fuel rich exhaust mixture.
 The  exhaust gases are oxidized by incorporating an ignition source (such as a  spark
 plug)  in  a muffler type container installed in the exhaust system.

 In some designs, the  catalytic, thermal, and afterburner approaches for oxidizing
 exhaust gas HC and CO also  indirectly reduce NOx.  Frequently, a fuel rich carburetor
 mixture inhibits NOx  formation, mainly  because of the lack of oxygen in the engine
 combustion chamber.   These  systems, however, require air to be pumped into the exhaust
 system to complete the oxidation of HC  and CO.

 The  purpose of exhaust gas  filters, such as Device 164, is to reduce or eliminate par-
 ticulate  emissions such as  lead, carbon, or soot from the exhaust  stream.  There are
 several approaches for removing particulates,  including mechanical filtering,  electric
 precipitators, cyclone separators, fiberglass  filters, and scrubber type devices.

 1.2.1.2   Induction Control  Systems

 Retrofit  devices of this type operate in general on the basis of either leaner air-
 fuel mixture ratio or improved distribution of the mixture.  Lean  fuel mixtures pro-
vide HC and CO reduction by reducing the amount of fuel taking part in the combustion
process or by increasing oxygen availability.   Although this same  effect could be
partially accomplished by adjusting the carburetor idle circuit to a lean mixture,
 some of the retrofit devices  studied provide lean mixtures under all engine operating
conditions.   Device 1 does  this by means of a variable valve that allows air to enter
the intake manifold as a function of the manifold vacuum.   Device 42 is another air-
bleed system which provides lean mixture, but in this model the effect of the air
(1)  All retrofit devices were assigned an identification number.  Refer to Table
     4-1 of this volume for summary descriptions.
                                        1-6

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bleed is to increase the air-fuel ratio during normal operation,  not during idle or
deceleration.  Device 317 combines air bleed with richened fuel intake under high
vacuum.

Device 33 provides leaner fuel mixtures by means of a carburetor modification in
which the fuel bowl is vented to the intake manifold rather than to the atmosphere
(as is the usual case).  In this case, the high manifold vacuum conditions which
occur at idle and deceleration reduce the pressure differential between the bowl
and the carburetor venturi, thereby tending to decrease the amount of fuel entering
the venturi.

The intake manifold modification systems depend on improved air-fuel distribution
as a means of reducing emission levels.  The intake manifold modification ap-
proaches (Devices 172, 430, and 440) use various intake manifold inserts (typically
between the manifold and carburetor) to either diffuse the air-fuel mixture or to
equalize distribution to the cylinders.  Other approaches, such as carburetor
modifications to improve the air-fuel mixture diffusion in the venturi section,
were offered in the program (Device 295).

Recirculating a portion of the exhaust gases back into the induction system reduces
peak combustion chamber temperatures, and is an effective method of reducing NOx.
For example, recirculating 15-20 percent of the exhaust gas and mixing it with the
intake gases may reduce NOx up to 60-80 percent.  Those exhaust gas recirculation
devices which were offered in this program also included disconnect of the
distributor vacuum advance as a method of further reducing the formation of NOx
and also enhancing the HC oxidation.

1.2.1.3  Ignition Control Systems

These retrofit types are based on two approaches to emission reduction.  First
the ignition timing modification approach uses the principle of retarding the
ignition spark which increases the exhaust gas temperatures to the point where
the exhaust will continue to burn in the exhaust manifold.  This is an alternate
way of accomplishing the same effect as that of the exhaust reactor systems.  In
addition, the combustion cycle peak temperatures are reduced, inhibiting NOx
formation.

Second, the ignition spark modification approach is based on the concept that
improved spark ignition, either through longer spark duration  (Device 259) or
higher voltage spark (Device 268) will improve combustion efficiency.

1.2.1.4  Fuel Modification

Fuel modification systems alter the normal combustion process by using different
fuels (other than gasoline) or by adding a fuel additive to gasoline.  Gaseous
fuel conversion systems are designed to prolong engine life and to lower emission
levels.  However, special tuning is required for lower emission levels.

Fuel additives are designed to clean up carburetor and engine deposits with mileage
accumulation or tend to keep deposit levels low when the engine and carburetor
systems are new.  In this program, fuel additives were not tested, because of the
substantial mileage accumulation required to show the effect of the additive in
reducing emissions.
                                         1-7

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1.2.2  Crankcase Blowby Emission Control Systems

Engine blowby results when the air-fuel mixture in the cylinder escapes past the
piston rings during the compression stroke.  A smaller amount of the blowby leaks
past the rings during the power stroke.  The blowby gases enter the crankcase and
subsequently escape to the atmosphere from an uncontrolled vehicle.

Crankcase control systems provide a means of circulating ventilation air through
the crankcase, mixing the air with the blowby gases, and recirculating the mixture
into the intake manifold through a variable or fixed orifice control valve.  The flow
rate through the valve is normally controlled by intake manifold vacuum.  Crankcase
ventilation air is drawn either directly from the engine compartment (referred to as
an open system), or from the engine air cleaner through a tubing into the crankcase
(a closed system).

Among the retrofit blowby control devices studied, Devices 170 and 315 are closed
systems.  Devices 160 and 427 can be installed as open or closed systems.  Devices
160 and 170 are currently accredited for use in California.  All of these devices
are basically the same, except that Devices 160 and 427 also have filters.

1.2.3  Evaporative Emission Control Systems

These systems control fuel evaporation from the fuel tank and the carburetor.  No
retrofit devices in this category were found to exist (except for the Device 165
combination system); however, a production fuel evaporative control system for new
model vehicles was evaluated for retrofit feasibility.

Gasoline tanks and carburetors are vented to the atmosphere on pre-1970 vehicles
sold new in California and on pre-1971 vehicles sold new nationally.  Losses at
the carburetor occur almost entirely during the hot soak period after shutting off
a hot engine.  The residual heat from the engine causes the temperature of the fuel
bowl to reach 150-200°F, resulting in substantial boiling and vaporization of the
fuel.

With high ambient temperatures (90-110°F), fuel tank temperature may increase up
to 120°F while driving or parked.  During driving, the hot air from the engine flows
beneath the car and increases the fuel tank temperature.  When parked over a hot
surface, fuel tank temperatures are also increased.  As a result, fuel evaporation
occurs through the tank vents.

In one type of evaporative emission control system installed on 1971 and later
model vehicles, the crankcase is used as a storage container for vapors from the
fuel tank and carburetor.  During the hot soak period after engine shutdown, the
declining temperature in the crankcase causes a reduction in crankcase pressure
sufficient to induct the evaporative emissions from the tank and the carburetor.
Vapors emanating from the carburetor are drawn directly to the crankcase, while
vapor from the fuel tank is first carried to a liquid-vapor separator.  The liquid
condensate returns to the fuel tank and the remaining vapors are drawn into the
crankcase.  When the engine is started, the crankcase is purged of the evaporative
emissions through the positive crankcase ventilation system.  A sealed fuel tank
with a fill-limiting device is required to ensure that enough air is present in the
tank at all times to allow for thermal expansion of the fuel.  A pressure/vacuum
relief gas tank cap is used to provide a safety valve for excess vacuum or
pressures in the fuel tank.
                                         1-8

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In the absorption-regeneration system, a canister of activated charcoal traps the
vapors.  During a hot  soak period, vapor from the fuel tank is routed to a liquid-
vapor separator, and liquid fuel is returned to the tank.  The remaining vapor,
along with  fuel vapor  from the carburetor, is vented through the canister filled
with activated charcoal  that traps the fuel vapor.  The vapors are purged from the
canister and drawn back  into the induction system for burning in the combustion
chamber during engine  operation.


A sealed fuel tank with  a fill limiting device is also required in this system to
allow for thermal expansion.  A pressure/vacuum relief gas tank cap is used with
this system to prevent excess vacuum or pressures in the tank.


 1.2.4  Emission Control  Combinations


Most of the retrofit devices evaluated combine two or more of the basic techniques
of emission control.  Because of the difficulty in classifying all combinations,
the emission control combination group was reserved for those devices combining two
or more of  the group level control functions; for example, exhaust with crankcase
emission control and/or with fuel evaporation emission control.  Combinations with-
in a group  were classified according to the major type of retrofit hardware re-
quired; thus a catalytic converter with vacuum advance disconnect was classified as
a catalytic conversion system within the exhaust gas control type, whereas an
exhaust gas recirculation system with vacuum advance disconnect was classified as
an EGR control within the induction modification type.

Under this  classification system, four retrofit devices were classifiable as
emission control combinations.   Device 165 combines control techniques for all
three sources of vehicle emissions.  Device 408 combines exhaust gas control with
blowby control.  Device 469 combines exhaust gas and particulate control.  The
fourth device (Device 59) was not described by the developer other than that it
controls all exhaust emissions.


1.3  RETROFIT DEVICE PERFORMANCE


The feasibility of using retrofit devices as a means of controlling emissions from
cars that are either partly or totally uncontrolled is determined by the effec-
tiveness and the costs of the devices.   Effectiveness is determined mainly by the
extent to which a device reduces vehicle emissions, and does so without causing
unacceptable drawbacks in vehicle driving quality and general operating safety.

Costs are determined by  the initial purchase price of the device, including the
cost of installing it on a vehicle, plus the subsequent cost of operating and
maintaining the vehicle with the device installed.  Operating and maintenance costs
                                        1-9

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of the installed devices are calculated by the change in vehicle fuel consumption,
by the number of times it may fail partly or wholly during the vehicle's operating
life, and by the frequency and type of maintenance required,  including the cost of
labor and materials.

1.3.1  Emission Reduction Effectiveness

All of the retrofit devices studied were evaluated for emission reduction effec-
tiveness in terms of their capability to reduce exhaust emissions - the source of
approximately 60 percent of vehicle HC emissions and essentially 100 percent of the
CO and NOx emissions.  The exhaust emission reductions of the devices were evalu-
ated by comparing test data measured on a standard vehicle without the device in-
stalled (baseline) with test data on the same standard vehicle with the device
installed (retrofit).

The mean emission reductions of the representative devices tested in the retrofit
program are shown in Figure 1-1.  These pooled mean reductions represent from 10 to
18 complete tests on each of the representative devices using the 1972 Federal Test
Procedure.  (Approximately half of the tests on each device were conducted in
California and the other half were conducted in Michigan.) Figure 1-1 illustrates
the pooled mean reduction that the representative retrofit systems can achieve, and
the confidence levels for these data are shown in Figure 4-1  (see paragraphs 4.1.1.2
and 4.1.1.3).

Figure 1-1 shows that catalyst systems with vacuum advance disconnect have the
greatest potential for reducing all three exhaust pollutants  (HC, CO, NOx).  Air
bleed to the intake manifold systems primarily reduce CO and, to a lesser extent,
HC.  The air bleed systems may show a slight increase in NOx  because of the added
availability of oxygen.  The ignition timing modification (spark retard) retrofit
device with lean idle adjustment is effective in reducing HC, CO and NOx.  The
exhaust gas recirculation system with vacuum advance disconnect is primarily an
NOx control device, but some reduction of HC and CO is also obtained.

The results for the devices that received limited testing in the retrofit program are
presented in Sections 4 and 5.  Some of the other systems which were not tested in
the retrofit program also showed substantial emission reduction.  These data were
supplied either by the retrofit developer (from a recognized test laboratory) or from
tests conducted by the Environmental Protection Agency.

Thermal reactor systems with air pumps and exhaust gas recirculation showed average
reductions of 80 percent for HC, 44 percent for CO, and 65 percent for NOx.  These
data are based on the EPA 9-cycle by 7-mode constant volume sampler test cycle.

A gaseous fuel (LPG) system showed an average emission reduction (based on 18 tests)
of 81 percent for HC, 85 percent for CO, and 65 percent for NOx.  Gaseous fuel sys-
tems have been found to have exhaust emissions of lower photochemical smog reactivity
than gasoline systems (refer to paragraph 4.1.1.4 for additional comments on this
subject).

Because previous studies have substantiated the potential of crankcase blowby and
fuel evaporative control systems for reducing the HC associated with those emission
                                        1-10

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  100 T
   90 --
80 --
O  70
UJ
ex.
to
   60 --
z
O  50
   40 --
^  30
x
UJ


I20
§  10 +
o
o
            18 TESTS
               CO
                   NOx
                            17 TESTS
                                CO
                                   NOx

  10 TESTS
                                                     NOx
    15 TESTS
                                                                    NOx
  -10-1-
           DEVICE 1

          AIR BLEED
          TO INTAKE
          MANIFOLD
                            DEVICE 96

                          CATALYTIC
                          CONVERTER
                          WITH VACUUM
                          ADVANCE
                          DISCONNECT
  DEVICE 175

IGNITION
TIMING
MODIFICATION
WITH LEAN
IDLE MIXTURE
ADJUSTMENT
  DEVICE 246

EXHAUST GAS
RECIRCULATION
WITH VACUUM
ADVANCE
DISCONNECT
                    (See Figure 4-1 for confidence levels)
         Figure  1-1.  POOLED MEAN EXHAUST EMISSION REDUCTION OF DEVICES
                        TESTED IN THE RETROFIT PROGRAM
                    (ANAHEIM AND TAYLOR RESULTS COMBINED)
                                    1-11

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sources, this aspect of the vehicle emission problem was  not studied.(1)   However,
devices in both categories were evaluated for their installation requirements  and
costs as retrofit methods, and exhaust emission data provided by developers  of
blowby devices were evaluated.

Approximately 20 percent of an uncontrolled vehicle's total hydrocarbon emission
comes from crankcase blowby.  Closed blowby control systems will control all of
the HC emissions at all operating conditions and will provide air ventilation  to
the crankcase.  Open blowby control systems will control  blowby emissions and
provide crankcase ventilation at most operating conditions.  At heavy engine loads,
some blowby could escape from the crankcase through the open oil fill cap.  The
quantity of escaping blowby would depend on the flow characteristics of the  blowby
control valve.  Since open blowby control systems are no  longer legal on new cars,
they would not be likely candidates for retrofit; their operational limits are
noted to caution future evaluators who may be involved in the selection of retro-
fit devices for use.

A potential problem with combination air bleed and blowby systems is that, if  im-
properly designed, they could cause excessively lean carburetion with resulting
"lean misfire" and "surge."

About 20 percent of an uncontrolled vehicle's total hydrocarbon emissions come
from the carburetor and fuel tank vents by evaporation of the fuel. Most of  these
emissions occur during periods when the engine is off. No retrofit fuel evapora-
tion control system was available for evaluation as a single approach to evapora-
tive loss control.  One retrofit system was a combination of exhaust, crankcase,
and fuel evaporation control, but no baseline emission data were provided by which
to calculate reductions.

1.3.2  Driveability and Safety

Information on driveability and safety was usually unavailable from retrofit device
developers, and that provided was, in most cases, unsubstantiated  as to test pro-
cedure.  Controlled driveability tests were conducted, however, on 11 devices
tested in the retrofit program.  In general, there were no driveability character-
istics that would cause any of the devices to be considered infeasible.  All of
the systems tested slightly degraded the operating characteristics of the vehicles;
however, a basic characteristic of most retrofit devices  is the compromise of
(1)  Representative studies that have been performed in blowby and fuel  evaporative
     emissions include the following:

          •  Rose, A.  H.,  and R. C.  Stahman,  "The Role of Engine Blowby  in Air Pollu-
             tion," Journal of Air Pollution  Control Association, Volume 11,  No.  3,
             pp 114-7, March 1961.

          •  Bennett,  P.  A., M. W. Jackson, C.  K. Murphy, and R.  A.  Randall,  " Reduc-
             tion of Air  Pollution by Control of Emission from Automotive Crankcases,"
             Selected SAE Papers on Vehicle Emissions, Volume 6,  pp 224-53, 1964.

          •  Wentworth, J. T., "Carburetor Evaporation Losses," SAE Technical Progress
             Series, Vehicle Emissions, Volume 6, pp 146-156, 1964.

          •  Wade, D.  T.,  "Factors Influencing Vehicle Evaporative Emissions," SAE
             Paper 670126, January 1967.
                                        1-12

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 optimum  driving and mileage performance  to provide a degree of emission reduction.
 Acceleration  times at wide open  throttle were generally between 5 and 10 percent
 slower.

 Fuel  consumption variations were measured during the 1972 Federal Test Procedure for
 emissions and  the results of the four devices that received up to 18 tests were as
 follows:

 The ignition  timing modification system  caused an average 10 percent less miles per
 gallon,  and the catalyst system with distributor vacuum advance disconnect had essen-
 tially no effect on gasoline mileage.  The exhaust gas recirculation system with vac-
 uum advance disconnect and the air-bleed-to-intake-manifold system caused an average
 miles-per-gallon increase of 7 percent and 4 percent, respectively.

 The exhaust gas control systems, such as catalytic and thermal reactors, were found
 to be relatively free of adverse driveability characteristics.  Since these devices
 have  to  operate at high temperatures (up to 2,000°F), they have potential safety
 problems unless adequately insulated.

 On cars  that already have lean carburetion, the air-bleed-to-intake-manifold retrofit
 systems  could  possibly cause excessively lean carburetor mixtures which might lead to
 surging  and hesitation problems.

 The ignition timing modification system  indicated a minor adverse effect on accel-
 eration, but appeared to present no additional safety or driveability problems.

 1.3.3  Reliability, Maintainability, and Inspection Requirements

All retrofit devices were found to have acceptable reliability and maintainability
 characteristics provided that conventional automotive design standards are applied
 to production  models.  Almost any retrofit component designed to normal automotive
 functional, cost, and production standards may be expected to exhibit a useful life
 of 50,000 miles or more, provided that good maintenance habits are followed.

Most of the retrofit devices evaluated in the program have acceptable periodic
maintenance requirements.  Most of these devices require 0.5 hour or less to main-
 tain,  and have a maintenance parts cost of $3.00 or less.   Maintenance costs are
generally higher for those devices incorporating ignition timing or spark duration
as a control technique if the whole unit must be replaced when failure occurs.  Only
two devices indicated maintenance requirements at less than 12,000-mile intervals.
About one-third of the devices evaluated indicated maintenance requirements only
after 25,000 or more miles.   The catalyst system tested in the retrofit program re-
quires a new charge of catalyst at 25,000-mile intervals at a cost of $20 for an 8-
cylinder engine and $15 for  a 6-cylinder engine.

Increased maintenance and reduced reliability imposed on the vehicle as a result of
a retrofit device was also evaluated.  For example, spark retard generally increases
temperature of gases passing through exhaust valves and may induce engine overheating.
Exhaust gas recirculation may cause induction system deposit buildup.   Use of cata-
lytic  reactors, thermal reactors, and afterburners poses potential problems of in-
creased exhaust system backpressure and increased temperature which may cause exces-
sive valve operating temperatures.   To investigate the long-term effect of some of
these  operating characteristics, durability tests were performed on four representa-
tive devices.   These tests will be documented in Volume VI.
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A periodic vehicle inspection program is recommended as a necessary part of any
program of vehicle emission control incorporating retrofit devices.  The purpose of
this program would be to ensure that the retrofit device functions effectively after
installation as well as during its lifetime.   Inspection of vehicles equipped with
retrofit devices would require measuring HC,  CO, and possibly NOx levels.  An emis-
sion limit would have to be established for each pollutant.  For those retrofit de-
vices and systems that perform as a function of engine speed, such as the ignition
timing modification type, the desired test procedure would have to simulate differ-
ent road speeds to provide complete evaluation of the installed retrofit system.  If
the exhaust control technique is independent of road-load conditions, then an idle
test may be sufficient.

Retrofit crankcase emission control systems should be subjected to an operational
check and a visual component inspection.  These devices may be inspected using crank-
case vacuum or pressure as a means of establishing failure levels.

There is no information on what would be the inspection requirement for retrofit fuel
evaporative emission control systems.  The pressure/vacuum safety relief systems
could be inspected with pressure gage instrumentation.

1.3.4  Initial and Recurring Costs

Initial costs consist of the material costs and labor costs necessary to complete a
retrofit installation.

Additional costs for engine tuneup prior to device installation must also be con-
sidered if this procedure is specified as part of the installation.  However, be-
cause of the contract exclusion of tuneup as a retrofit method, only the tuneup
requirements directly related to the retrofit device installation were considered.

Recurring costs are those associated with retrofit repair and maintenance.  Fuel
consumption increase or decrease, where it was known, was also included in this
category.

The initial costs of the more effective devices were generally higher than the less
effective devices.  For example, the initial cost of the catalytic converter with
vacuum advance disconnect, which controls all three pollutants, was reported to be
$175, including an air pump.  At the other extreme, the less effective air-bleed-to-
intake-manifold systems ranged from $23 to $64.  For the NOx control systems, ignition
timing modification and exhaust gas recirculation, initial costs ranged from $45 to
$89.

Because the gasoline mileage factor is a sensitive factor in the amount of recurring
cost, it should be accurately determined prior to drawing final conclusions .on the
total costs of any particular retrofit method.  When recurring costs were computed
in the retrofit study, the effect of fuel consumption changes were included  for those
devices which were tested.  This effect was excluded from the recurring cost of the
other evaluated systems because most developers did not submit fuel consumption data,
and many of those who did submit data reported improvements in economy which were
questionable.
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1.3.5  Installation Skill Level and Training Requirements

Analysis of the detailed installation and adjustment procedures for retrofit devices
showed that most retrofit system types would require a skilled automotive mechanic
to perform the installation.  The principal consideration in this requirement is the
need for regulated quality control of device installation and subsequent mainten-
ance, inspection, and repair.  It is essential that device installation include
emission testing to verify that the emission control effectiveness of a device is
achieved (see paragraph 4.3.3).

The physical installation of the devices evaluated requires normal automotive mech-
anic skills.  However, most auto mechanics are not presently trained to properly
adjust a retrofit device and related engine tuneup parameters for low emissions.
Technician upgrading and training programs would be required for a successful and
effective retrofit program.  Such training would provide certified mechanics to
operate licensed retrofit installation and maintenance centers.  Further, the
training would also provide the inspectors for quality surveillance of the retrofit
program.

1.4  EVALUATION METHODOLOGY

The relative effectiveness and costs of retrofit devices were analyzed by means of
an evaluation methodology which quantitatively and qualitatively considered all
significant device performance parameters and criteria.  This methodology was
structured in three general segments for evaluation.  These segments were criteria,
performance, and cost effectiveness, each providing successively refined evalua-
tions.  The basic evaluation criteria used in the retrofit program are listed in
Table 1-2.

The emission standards and installation cost criteria used in this study were
identical to those specified by law in California's used car standards.  The used
car emission standards were applied only to the 7-mode exhaust emission test data
supplied by the developer  (see Note 1 in Table 1-2).  Other criteria, such as the
installation and maintenance labor rate, were developed on the basis of standards
in the automotive industry.  These criteria can be adjusted by States and other
agencies responsible for vehicle emission control to meet their special require-
ments.

Results of the evaluation methodology are summarized in Section 5.

1.5  DEVELOPMENT STATUS AND APPLICABILITY

Most retrofit devices are available in at least the prototype form.  At least 25
devices are either being marketed or are ready to be marketed.  Some are being
marketed for purposes other than emission control, such as improved engine perform-
ance.  The study indicated that several devices could become readily available
shortly after there is a clear definition of specific standards or criteria, if
these criteria are less stringent than California's.
                                        1-15

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          Table 1-2.   PERFORMANCE PARAMETERS AND EVALUATION CRITERIA
                 FACTOR
                                                             CRITERIA
1.  Emission Index Factors
    a.  Emission standards  (1)

                HC
                CO
                NOx
    b.  Emission baseline


2.  Driveability and Safety Index  Factors

    a.  Safety

    b.  Critical driveability



    c.  General driveability


3.  Cost and Cost-Related Index  Factors

    a.  Installation cost (including  kit)


    b.  Recurring cost


    c.  Reliability


    d.  Maintainability


    e.  Availability
Less than 350 ppm or 4.5 gm/mi
Less than 2.07, or 47.6 gm/mi
Less than 800 ppm or 3.0 gm/mi

No increase of any pollutant beyond an allow-
able experimental error (2)
No hazardous conditions

No stall on acceleration
No hot idle stall
No backfire

Driveability Index less than 1.0 (refer to
para. 3.1.5)
Less than $85.00, including labor at $12.50
per hour (3)

Less than $15.00 per year ($0.125 per 100
miles) (4)

At least 50,000 miles of operation before
total failure

At least 12,000 miles of operation before
periodic maintenance is required

Less than 1 repair hour per 12,000 miles of
operation (4)
(1) The volume concentration values  are  the  California used car device accreditation
    standards as specified in California Health and Safety Code Chapter 4, Article 2,
    paragraph 39107 (refer to Volume IV, Appendix E).  These standards are for the
    7-mode cold-start test cycle specified in  the 1970 Federal Test Procedure  (see
    pertinent comments and cautions  in Volume  III, Section 5.1).  The grams per mile
    (gm/mi) correlated with the  above standards were calculated for a 4,000-pound
    vehicle in accordance with the method  set  forth in the 1970 Federal Test Pro-
    cedure.  If the evaluator intends to use the  1972 Federal CVS Test Procedure,
    appropriate used car standards must  be established for that test procedure.

(2) In this report, an experimental  error  of +10% was used.

(3) $12.50 per hour based on California  repair labor average.

(4) Average miles driven per year assumed  to be 12,000 miles.
                                           1-16

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The retrofit evaulations conducted in this study were primarily aimed at uncontrolled
vehicles, which were not originally equipped with exhaust control devices (pre-1968
nationally and pre-1966 in California).  However, some retrofit methods are applicable
to vehicles which already have partial exhaust control devices installed as original
equipment (1968 and later model-year cars nationally and 1966 and later model-year
cars in California).

Almost all of the retrofit exhaust control systems evaluated are applicable to pre-
1968 domestic vehicles with varying degrees of emission reduction effectiveness.
In general, retrofit systems are not yet available for foreign used cars.

The study showed that the catalytic converter systems might be applicable for
retrofitting all used cars.  Exhaust gas recirculation systems would be applicable
to both uncontrolled and partially controlled cars.  Distributor vacuum disconnect
would also be applicable to both groups of cars.

Air bleed to intake manifold systems can be easily retrofitted to both controlled
and uncontrolled vehicles.  However, on vehicles which are already factory equipped
with exhaust and crankcase blowby control systems, the use of air bleed retrofit
systems may cause excessively lean carburetion that may lead to lean misfire.

In summary, it cannot be concluded that retrofit technology is directly applicable
to 1968 and later model-year.cars without further testing of individual devices.
However, some of the retrofit methods evaluated may be feasible on these cars.

Of the devices evaluated, seven have been specifically developed for used car
retrofit to the extent necessary for approval in California, the only State pres-
ently with a specified retrofit program and used car emission standards.  These
devices were approved by the California Air Resources Board and are currently being
developed or produced for mass marketing in California.  Device 175, the ignition
timing modification system tested in the retrofit program, was accepted in November
1971.  Devices 160 and 170, crankcase blowby controls, were accepted in 1963 and 1965,
respectively.  The other four (Devices 52, 459, 460, and 466) are all gaseous fuel
systems approved since 1969.

1.6  GUIDELINES FOR SELECTING AND IMPLEMENTING FEASIBLE RETROFIT METHODS

The implementation of a retrofit method of vehicle emission control must consider
the present and future requirements with respect to changing vehicle control condi-
tions, to ensure a continuous, satisfactory program.  The recommended steps for
implementation are:

     a.  Defining the emission reductions required from the used car population.

     b.  Defining the characteristics of the used vehicle population to which retro-
         fit methods are applicable.

     c.  Identifying candidate retrofit methods for application to that vehicle
         population.

     d.  Determining which retrofit methods are most cost effective for the emission
         controls to be implemented, giving due consideration to facilities and labor
         requirements for implementing the retrofit program.
                                        1-17

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     e.  Identifying the retrofit device certification program.

     f.  Conducting the cost effectiveness studies required to verify the retrofit
         approach as being the most appropriate method of emission control.

     g.  Preparing an implementation plan.

     h.  Initiating and maintaining the implementation plan.

The evaluation methodology developed through this study should provide an essential
tool in the planning and implementation of optimum retrofit programs.

A retrofit device is feasible if its overall effectiveness in reducing emissions and
maintaining reasonable driving quality is sufficient to justify the costs of obtain-
ing that effectiveness.  More specifically, the feasibility of a retrofit device
depends on its effectiveness and costs for particular emission control applications.
A device might appear infeasible when compared with other devices because of the
fewer number of pollutants it controls or the lesser magnitude of control it achieves.
However, it could be entirely adequate for a particular emission control situation in
which the scope and magnitude of control offered by the device is exactly what is
needed.  Ultimately, therefore, retrofit device feasibility depends on the emission
control situations faced by individual air quality control regions.

In addition, the success of a retrofit program depends heavily on the availability of
the required facilities for installation and maintenance of the retrofit devices.

1.7  RECOMMENDATIONS

The following programs are recommended as future research and development efforts in
support of retrofit method implementation:

     a.  The applicability of retrofit methods to vehicles factory equipped with emis-
         sion control techniques should be studied as a means of achieving maximum
         continuity of the retrofit approach.   An example of this recommendation would
         be to retrofit and evaluate NOx type control devices on 1966 through 1970
         model cars in California and 1968 through 1972 vehicles elsewhere in the
         nation.

     b.  The maintenance requirements of the cost effective retrofit devices will
         require that provisions for a maintenance inspection program be planned and
         implemented concurrently with the promulgation of any legislation requiring
         the use of retrofit devices on a mandatory basis.  A study should be imple-
         mented to determine the procedures, criteria, personnel, instrumentation,
         facility, and training requirements of a maintenance inspection program to
         support any mandatory use of retrofit devices.  This program would be de-
         signed to ensure that the inherent cost effectiveness of a retrofit device
         is not compromised by inattention to maintenance requirements of the device.

     c.  Upgrading of the automotive service industry through supplemental training
         programs would be required to provide correct tuneup adjustments to vehicles
         with retrofit devices installed.   The scope and requirements of such upgrad-
         ing should be studied and specified for the principal types of devices.   The
         cost impact of an upgraded service industry on the cost effectiveness of
         retrofit devices should also be determined.
                                        1-18

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2 - RETROFIT PROGRAM
      APPROACH

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                                    SECTION 2

                             RETROFIT PROGRAM APPROACH


The program objective to determine what methods of emission control can be feasibly
retrofitted to light duty used cars required that the retrofit program approach be
directed toward determining the effectiveness and costs of retrofit devices.   This
was accomplished by means of a comprehensive retrofit method and developer data
survey, system tests, and engineering analysis.  The data survey provided informa-
tion of varying levels of completeness from all sources of available information on
retrofit methods and developers that could be identified.  The system tests provided
a set of emissions, fuel consumption, and driveability test data from two widely
separated geographical areas in the U.S. for a range of representative retrofit
devices that could be tested within the schedule constraints of the program.   The
engineering analysis provided system descriptions of the devices for which adequate
data were obtained through the data survey and the system tests.  The results of
this analysis were combined with the emissions and other performance data to
provide quantitative inputs to the performance analysis of each retrofit method.

2.1   RETROFIT METHOD SURVEY

The retrofit program was initiated by performing a thorough search for all sources •
of information on retrofit methods and developers.  The objective of the retrofit
method survey was to search all reliable sources for available information, and to
assemble as much relevant information as possible on retrofit emission control tech-
niques existing for light duty vehicles.  This information survey encompassed
present and potential emission control retrofit methods applicable to pre-1972
motor vehicles in the light duty gasoline-powered class  (less  than 6,000 pounds
gross vehicle weight).  This search was performed on an international scale.  Each
potential source of information about retrofit devices being produced or manufactur-
ed was sent a letter describing the purpose of the program and requesting their
participation in the program.  Each respondent expressing interest in participating
and who was an actual candidate retrofit method developer was sent a request to
provide data on his device.  These data were used to screen the devices by type of
retrofit method, and to rank them based on their feasibility.  The most feasible
and representative devices were selected for the retrofit test program.

The Air Pollution Control Association (APCA) Directory and the Society of Automotive
Engineers (SAE) Roster Issue were used initially to identify retrofit developer
sources.  Additional source identifications were made utilizing:

          Environmental Protection Agency (EPA) files
          California Air Resources Board (ARE) files
          Olson Laboratories Testing Services files
          Inquiry to air quality agencies at Federal and State levels
          A patent search conducted by the Northrop Legal Staff
          A general news release.
                                        2-1

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The approach to the retrofit method survey consisted of the following steps:

     a.  Identifying the sources of retrofit devices.

     b.  Transmitting a letter of inquiry to these sources, requesting'their partici-
         pation in the program or the identification of other retrofit developer
         sources. (The developer was requested to submit a letter of intent to
         participate in the retrofit program.)

     c.  Transmitting a survey questionnaire to interested sources to obtain detailed
         information about the technical and cost characteristics of their respec-
         tive retrofit devices.

     d.  Recording of data questionnaire responses.

The data survey questionnaire was designed to obtain from the retrofit method de-
veloper the full scope and depth of information required to perform a comprehensive
system analysis and evaluation of the device submitted.  The questionnaire was
structured to provide qualitative and quantitative data in the following categories:

     a.  System Information - Including system technical description, emission con-
         trol category, development status, and vehicle adaptability.

     b.  Performance Data - Including emission reduction, reliability, maintaina-
         bility, and driveability.

     c.  Cost Data - Including initial and recurring costs.

     d.  Marketing Plan

2.2  RETROFIT METHOD SCREENING EVALUATION

The information obtained from each retrofit developer source that responded favor-
ably was reviewed to identify the device category, level and reliability of emission
reduction, availability of device for testing, cost, and the adequacy of data by
which to perform a complete system analysis of the device.  This information was
tabulated for each device to establish an overall preliminary ranking of devices.
The test candidate devices were identified on the basis of how well they represented
the generic retrofit groups, on average emission reduction potential, on development
status, on availability for testing, and on cost.  Members of the OLI-Northrop-EPA
Technical Review Board then reviewed the test candidate retrofit systems and made the
selections of the devices that would receive evaluation in the test program.  The
remainder of the candidate systems received an engineering analysis by a Northrop-
Olson staff of engineers from the data supplied by the retrofit developer.

Table 2-1 lists those retrofit system types which were candidates for the test pro-
gram.  Crankcase blowby control devices were eliminated from test evaluations because
adequate data were already available for the engineering evaluation.  Fuel additives
were also eliminated from the laboratory test evaluation because the required mile-
age accumulation to show the emission reduction effects was beyond the scheduled
time limits of the study.

Nine systems were selected for evaluation on two vehicles.  After the initial selec-
tion the device manufacturers were notified.  One of the selected device manufacturers
                                        2-2

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      Table 2-1.  RETROFIT SYSTEM TYPES TESTED IN RETROFIT PROGRAM
DEVICE
NO. (1)
DESCRIPTION
Up to 18 Tests Per Device
1
96
175
246
Air Bleed to Intake Manifold

Catalytic Converter with Distributor Vacuum Advance
Disconnect
Ignition Timing Modification with Lean Idle Adjustment
Speed-Controlled Exhaust Gas Recirculation with
Advance Disconnect
Vacuum
Up to 3 Tests Per Device
10
33
42
69
245
288
295
Throttle-Controlled Exhaust Gas Recirculation with
Vacuum Advance Disconnect
Carburetor Modification, Main Jet Differential
Air Bleed to Intake Manifold
Electronic-Controlled Vacuum Advance Disconnect
Carburetor Lean Idle Modification
Variable Camshaft Timing
Carburetor Main Discharge Nozzle Modification
Carburetor with Variable Venturi
Pressure

and



(1) Devices evaluated are identified in Table 4-1.
declined to participate and one system was not available during the test period.
Four retrofit systems were selected to receive evaluation on 13 test vehicles.  De-
tailed selection procedures and identification of the retrofit systems that were
evaluated in the test program are presented in Volume III,  Section 4.

2.3  ENGINEERING ANALYSIS

The purpose of the engineering analysis of retrofit control devices was to (1) deter-
mine the acceptability of the data provided by the development sources, and (2),
when possible, develop additional or supplementary data that could be used as inputs
to the evaluation methodology.  The approach for the engineering analysis was to
initiate the preparation of retrofit system descriptions from the information obtained
through the retrofit method survey and the test program.  These descriptions were
used in the performance analysis.  Each system description included physical,
                                        2-3

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functional, and performance characteristics; driveability, maintainability, and
safety analyses; installation description; initial and recurring costs; and a feasi-
bility summary.  Detailed system performance parameter analyses descriptions were
prepared by a team of engineers representing the key technologies of retrofit device
design.  A discussion of the system description format and the approach to perform-
ance parameter analysis is presented in Volume III, Section 4.

2.4   TEST PROGRAM

A summary of the test vehicle fleet, test requirements, and test approach for the
retrofit test program is presented in the following subparagraphs.   The detailed
test procedures are presented in Volume IV, and the test results are presented in
Volume III.

2.4.1     Test Vehicle Selection

The contract called for a maximum of 24 cars to be divided into two replicate fleets;
half in Taylor, Michigan,  and half in Anaheim, California.

The rationale for the replicate fleets was to isolate retrofit system performance
differences, if any, which could possibly be attributable to driving conditions,
geographical location, and vehicle climatological exposure history  at two dispar-
ate locations in the U.S., and any possible bias in testing facilities and
personnel.

Table 3-1 of Volume IV briefly describes the test fleet by model year, engine size,
and location.  The California and Michigan fleets were identical in most respects.
Backup vehicles were purchased to replace some of the initial fleet in the event of
major vehicle failures.

Prior to the purchase of a test vehicle, an intensive screening inspection was con-
ducted.  First, an overall vehicle inspection included a visual check of safety
related items such as tires, wheel alignment and brakes.  Second, the vehicle
received an engine condition inspection.  Measured blowby flow rates were compared
to the California Blowby Procedure (Volume IV, Appendix F).  Cars were selected
which had normal blowby flow rates within the fourth to seventh population decile.
Cranking compression pressures were measured.  If the cylinder compression pressures
measured within a range of 10 psi between cylinders, the car was acceptable.  The
engine condition criterion was to accept cars which were in reasonable condition and
would not need any major engine repair throughout the test program.  Hydrocarbons
and carbon monoxide emission levels were measured at idle and at 2,500 rpm (free
running).  These data were used to diagnose the condition of the carburetor prior
to tuneup procedures.  Ignition system malfunctions were determined with an ignition
analyzer scope.  The vehicles were accepted if they met the overall vehicle and
engine condition criteria.  However, carburetor and ignition system malfunctions
were not grounds for rejection.

2.4.2     Test Program Procedures

As each vehicle was procured, an "as received" exhaust emission test and a drive-
ability test were conducted.  It was then tuned to the auto manufacturer's specifi-
cations to minimize the possibility of tuneup malfunction during the subsequent
retrofit system tests and to establish a reproducible baseline.  The basic
objective here was to evaluate the performance of the retrofit device, not the
effect of tuneup.  The vehicle then received a series of baseline  (after tuneup)

                                        2-4

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exhaust emission tests and driveability tests.  After each baseline test,  the
vehicle was equipped with the candidate retrofit system for exhaust emission
and driveability tests.  The tests alternated between the baseline and retrofit
system tests until testing of all candidate systems was complete.

The 1972 Federal Test Procedure was used to measure the exhaust emissions  of the
baseline and retrofit vehicles.(1)  The Federal exhaust emission tests consist of
prescribed sequences of fueling, parking (cold soak), dynamometer operating condi-
tions, sampling, and analytical calculations.  The exhaust test is designed to
determine hydrocarbon, carbon monoxide, and oxides of nitrogen on a mass emissions
basis while the vehicle is simulating an average urban type trip of 7.5 miles.
Following a 12-hour soak with the engine off, the test vehicle is "driven" on a
chassis dynamometer through a prescribed driving schedule.  All of the exhaust gas
is collected and diluted with air, and then routed through a constant volume sampl-
ing (CVS) system.  A proportional sample of the diluted exhaust emissions  is collect-
ed continuously in an inert plastic bag for subsequent concentration analysis and
the analytical calculations.  After the driving cycle is completed, the diluted
exhaust sample is analyzed for volumetric concentrations of hydrocarbons,  carbon
monoxide, and oxides of nitrogen.  Mass emission levels are then calculated using
applicable pollutant gas densities and correction factors.

Fuel consumption was measured during the baseline and retrofit exhaust emission
tests.  The fuel consumed during the driving cycle was measured by weight.  The
net amount of fuel consumed during the test was calculated and converted to miles
per gallon.         ^

The Automobile Manufacturers Association (AMA) standard driveability test procedure
was used to evaluate the operating characteristics of the vehicle on the road
(refer to Volume IV, Appendix G).  Basically, the procedure consists of a cold
start driveaway following an overnight soak period.  A hot start driveaway procedure
follows the cold start driveability tests.  The cold start evaluation consists of
engine startup, idle, and part throttle and full throttle acceleration modes up to
30 mph.  The hot start consists of a series of cruise, acceleration, and idle
modes of operation, and hot  start restart  evaluations.

The quality of each driving mode was noted by the driver and recorded by an observer
during each mode of operation.  Vehicle performance was determined at wide open
throttle from 0-60 mph by measuring the elapsed time.  Driveability tests were also
performed to determine whether environmental extremes (such as high altitudes and
low temperatures) had any significant performance effect on vehicle driveability
when a retrofit device was installed.

The durability tests consisted of driving the retrofit device equipped cars for
25,000 miles and measuring the exhaust emissions at 5,000-mile increments.  Mileage
accumulation was performed on a test route which consisted of freeway, urban, and
suburban driving at an average speed of approximately 35 mph.  Fuel consumption and
driving anomalies were recorded daily.
(1)  Federal Register Volume 35, Number 219, Part II, dated 10 November 1970.  The
     test procedure for NOx evaluation was published subsequently in Federal Register
     Volume 36, No. 128, Part II, dated 2 July 1971.
                                        2-5

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2.5  PERFORMANCE ANALYSIS

Data developed through the engineering analysis and system tests were utilized to
evaluate the candidate retrofit systems for their relative effectiveness and costs.

A mathematical methodology was developed to organize the many effectiveness and cost
variables for uniform and objective evaluations.  This model was implemented on IBM
Model 360/65 and 370/165 computers in H-level FORTRAN.  Data obtained from the sys-
tem tests and from the engineering analysis were processed through the methodology's
qualitative and quantitative analysis of each retrofit system.

The methodology itself was a beneficial byproduct of the retrofit study, and is
summarized more fully in the next section.
                                        2-6

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3 - EVALUATION
 METHODOLOGY

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                                    SECTION 3

                              EVALUATION METHODOLOGY


A major  objective of the retrofit study was to compare the overall performance of
the various devices relative to each other.  Quantitative indexes were developed
so that  an objective evaluation could be made and the devices numerically ranked.
Three principal numeric indexes - criteria, performance, and cost effectiveness -
were developed.  The detailed evaluation methodology is presented in Volume III,
and is summarized below.

The evaluation methodology  is structured in three equations:

      a.  Criteria Index:   This is a qualitative index designed to provide a
          gross indication  of whether a particular device meets the various
          legally imposed constraints such as emission reduction effective-
          ness, cost, and useful life., as well as fundamental customer de-
          mands such as gross safety and vehicle performance requirements.

      b.  Performance Index:  This index quantitatively evaluates the per-
          formance of the device.  It is composed of the weighted sum of
          an emission reduction index, a driveability index (what the device
          does to the vehicle operation), and a cost index.  The performance
          index provides a more refined evaluation of device performance.

      c.  Cost Effectiveness Index:  This index is the ratio of the emission
          reduction index to the cost index (both are from the performance
          index expression).  It provides a measure of the emission reduc-
          tion a given device would achieve for the money expended.

3.1  CRITERIA INDEX

The Criteria Index screens a device for a "yes" or "no" answer as to its basic fea-
sibility.  The Criteria Index can be expressed as a product of terms, each of which
has a value of either 1 or 0.  It provides the evaluator an indicator as to whether
a device will meet the various legislated constraints or limiting values specified
for each performance parameter.

If the Criteria Index calculation is 1, it means the device has met the legal and
implicit requirements for all criteria factors.  If the Criteria Index calculation
is 0,  it means the device did not pass one or more of the specified requirements.
The device is thus flagged as being substandard for at least one of the given set
of criteria used.   Some of the limits, however, may be flexible to allow for cri-
teria changes due  to differences in State or regional air quality control require-
ments.
                                        3-1

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The  Criteria  Index  comprises  the  following  factors:

                                  Emission Factors

      1.   Emission standards -  for HC, CO, and NOx

      2.   Emission baseline -  prevents emission  increase

          -—              Driveability and  Safety Factors

      3.   Safety  - device affects  vehicle operation and occupant safety

      4.   Critical driveability -  stall on acceleration,  idle,  or  backfire

      5.   General driveability - vehicle operation degradation due to device
          installation

                           Cost and Cost Related Factors

      6.   Installation cost -  initial cost of parts and labor

      7.   Recurring  cost - incremental costs related to device upkeep following
          installation

      8.   Reliability - mileage to partial or total failure of device

      9.   Maintainability - required periodic maintenance

     10.   Availability - time  inconvenience  to car owner  due to device failure.

A check is easily made of the above terms to determine which one is causing a
Criteria  Index of zero.  A decision can then be made regarding the significance of
the  problem.  The Criteria Index  is a gross screening process and may be used to
exclude the device  from further evaluation.

Detailed  definitions of the Criteria Index are presented in Section 3 of Volume III.

3.2   PERFORMANCE INDEX

The  Performance Index provides a  quantitative evaluation of a device.  The Perform-
ance  Index  (PI) shows whether the emission reduction benefit of a device is rela-
tively greater than its cost and  driveability penalties; and how much greater the
benefit is.

The  PI is represented by a summation expression to obtain relative and quantitative
ratings of the devices under evaluation.  This expression allows evaluation of a
device even if it does not pass certain State or regional evaluation criteria.


The  PI expression comprises three terms, each of which is quantified by a different
unit  of measure.  The first term  is the Emission Index.  It has no dimension, since
it is expressed as a per unit reduction.  The second term is the Driveability Index.
It is measured by rating points based on the driver's observation of various vehicle
operating characteristics.   The third term is the Cost Index, which carries the units
of dollars per 100 miles.


                                        3-2

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In order to add these individual indexes together, scaling factors (Si)  have been
included to establish a common measurement scale.   Weighting coefficients (C^)  are
required to reflect the evaluator's choice as to the relative degree of  importance
given to each index.

The overall Performance Index is expressed by the following equation:


; Emission \
Index \
Per Unit I - C
Reduction/

(DriveabilityX
Index ] - C~
Points /

(Cost \
Index
$/100 Miles/
Cj_ + C2 + C3

The Emission Index is the sum of the weighted percentage reduction of each of the
considered pollutants.  Emission tests are conducted both with and without the
device installed to determine the emission reduction benefit.  The Driveability
Index is determined by assessing what might be considered demerits for abnormal
driving characteristics (rough idle, detonation, surge, etc.).  Again, the tests
are conducted with and without the device installed to determine the degradation in
driveability.

The Cost Index combines the initial costs of the device and the recurring costs.
Cost Index parameters are measured in terms of the retail cost of the device in
dollars, the installation cost (based on number of hours to install times the
hourly labor rate), the cost of maintenance, the cost of repair, and the cost of
operation over the estimated service life of the device.

To compute the overall Performance Index, experienced judgment must be exercised in
assigning the three weighting coefficients, C^, C2 , and C%.  The coefficients given
to the Emission, Driveability, and Cost Indexes can greatly influence the relative
ranking of the devices.  For example, if one were to weight driveability by a high
coefficient, as compared to a low coefficient used to weight the Emission Index and
Cost Index, a device with high driveability rating could be ranked relatively higher
than the more cost effective devices.  If driveability is the evaluator's major con-
cern, then such weighting is proper.  However, one must be aware of the effect that
the weighting coefficient decision can have on the relative ranking of the devices.
The rationale for establishing coefficients used in this program is discussed in
Volume III, and it is important to recognize that these values represent the best
judgment of the study personnel.  The equations were designed so that the coeffi-
cients could easily be changed depending on the judgment of the specific emission
control agency using this evaluation methodology.

3.3  COST EFFECTIVENESS INDEX

The Cost Effectiveness Index (CEI) is intended to provide additional information to
complement the Performance Index.  Should two or more devices have essentially
similar Performance Indexes, the one with the highest Cost Effectiveness Index would
be preferred.  Cost effectiveness is usually defined as the rate of the desired
results or the desired output versus the required cost input.  In this case the CEI
is defined as the ratio of the Emission Index to the Cost Index.  In evaluating an
emission control device, the desired output is the per unit reduction of the
objectionable pollutant (Emission Index).  The required cost input may be expressed
                                        3-3

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as the total cost in terms of dollars per 100 miles driven (Cost Index). The Cost
Effectiveness Index (CEI) is expressed by the equation:

                Emission Index, per unit reduction
                    Cost Index, $/100 miles

3.4   SENSITIVITY ANALYSIS

A sensitivity analysis of the Driveability and Cost Indexes was conducted (see
Volume III, paragraphs 6.2.2 and 6.3.4).  Among all parameters measured for these
indexes, a change in fuel consumption showed the most sensitivity.  To illustrate,
a 10 percent loss in fuel consumption caused by a device would increase the Cost
Index by 62 percent.  A 20 percent change in the other terms of the Cost Index
would change the Cost Index by 10 percent or less.  A 20 percent change in the
various Driveability Index terms could cause a Driveability Index degradation up
to 13 percent.
                                        3-4

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4 - RETROFIT DEVICE
   EVALUATIONS

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                                     SECTION 4

                            RETROFIT DEVICE EVALUATIONS


Each retrofit device studied was evaluated to determine the effectiveness with which
•emissions are controlled, the influence of such control on vehicle operating perform-
ance, and total costs.  This evaluation was performed on those devices for which ade-
quate information either could be obtained from the retrofit developers of the devices,
or could be developed by test and analysis within the time frame of the study.  Based
on data obtained or developed in this way, it was possible to evaluate 65 devices in
varying degrees of completeness.  These devices are listed in Table 4-1 by the control
number used to identify each during the study.  The system description for each device
evaluated is presented in Volume II (see Appendix B).  Volume V includes a list of all
known retrofit developers, each of whom was invited to participate in the program.
The effectiveness and costs of the devices evaluated are summarized in the following
paragraphs.

4.1  EMISSION REDUCTION

Eleven devices were tested using the 1972 Federal Test Procedure.(1)  The average emis-
sion levels obtained for each device in these tests are listed in Table 4-2.

Use of these data in evaluating the emission reduction effectiveness of the devices has
to consider that the reliability and significance of the data depends on the type of
emission test procedure by which the data were measured and the number of tests that
were performed.  As shown by Table 4-2, the type and number of tests vary considerably
among the devices evaluated.  The higher the number of tests, the more reliable the
emission data are.  The 1972 Federal Exhaust Emissions Test Procedure is currently the
most representative test for actual driving conditions and also the most accurate for
determining the actual amount of automotive pollution being emitted to the atmosphere.

Table 4-3 lists the same devices by related retrofit categories, based on the similar-
ity of the emission control approaches employed.  Up to 18 tests were performed on one
retrofit device from each of the following representative types within the Exhaust
Emission Control Systems Group:

     a.   Exhaust Gas Reactors;  CO and HC are oxidized to nonpolluting carbon
          dioxide and water either by catalytic or thermal reaction.

     b.   Exhaust Gas Recirculation with Distributor Vacuum Advance Disconnect;
          The recirculated gas and spark retardation decrease peak cycle tempera-
          ture, thus inhibiting NOx formation.  Spark retardation also produces
          higher exhaust gas temperature, which results in greater HC oxidation.
(1) Refer to footnote, page 2-5.
                                         4-1

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                 Table  4-1.   DEVICES  EVALUATED  IN  THE  RETROFIT  PROGRAM
 DEVICE
  1 (1)
    (2)

 10 (2)
 22 (1)

 23 (1)

 24 (1)


 31



 33 (2)



 36 (1)


 42 (2)
 52  (1)
    (3)
 56
 57
59
62  (1)

69  (2)
93 (1)
95 (1)
                        DEVICE TITLE
Air Bleed to Intake Manifold:   Air bleed  to
intake manifold through adjustable valve  open
to ambient airflow.
Throttle-Controlled Exhaust  Gas Recirculation
with Vacuum Advance Disconnect:  Carburetor
fuel vaporization modification, combined with
throttle-position controlled exhaust gas  re-
circulation through intake manifold; and with
temperature-controlled  vacuum advance dis-
connect.
                           Electronically reg-
                          Electronic modifi-
 Electronic Fuel Injection:
 ulated fuel injection.
 Electronic Ignition Unit:
 cation to coil.
 Heavy Duty Positive Crankcase Control Valve
 with Air Bleed:   Crankcase  blowby gas control
 with air dilution.
 Thermal Reaction by Turbine Blower Air In-
 jection:  Air injection  into conventional
 exhaust manifold by means of air turbine
 operating off intake vacuum.
 Carburetor Modification, Main Jet Differential
 Pressure:  Carburetor fuel  bowl vented to in-
 take manifold rather than atmosphere by means
 of tubing with adjustable valve.
 Fuel Conditioning by Exposure to Electromagne-
 tic  Field:  Intake  fuel  routing through
 magnetic field.
 Air  Bleed to Intake Manifold:  Air bleed from
 air  cleaner to intake manifold through tub-
 ing  with adjustable valve.
 LPG  Conversion:   Liquified  petroleum gas (LPG)
 conversion.
 Crankcase Blowby  and Idle Air Bleed Modifi-
 cation:   Heated  air bleed through special idle
 jets,  combined with heated  Crankcase blowby
 into intake manifold.
 Air  Bleed with Exhaust Gas  Recirculation and
 Vacuum Advance Disconnect:  Bleeds combina-
 tion of  exhaust gas and  filtered ambient air
 to intake manifold,  with temperature-control-
 led  distributor vacuum advance disconnect.
 Three-Stage  Exhaust  Gas Control System:  (4)
 Catalytic  Converter:  Replaces standard
 muffler.
 Electronic-Controlled Vacuum Advance Dis-
 connect and  Carburetor Lean  Idle Modification:
 Electronic control  of distributor vacuum ad-
 vance  during  idle through 1,600 rpm and dur-
 ing  braked deceleration with temperature-
 controlled override and lean air-fuel mixture
 by modifying air screws.
Catalytic Converter with  Exhaust Gas Re-
circulation, Spark Modification,  and Lean Idle
Mixture:  Catalytic reactor  with air pump and
exhaust gas recirculation, plus special igni-
tion system and lean air-fuel  mixture.

 Ignition Spark Modification:  Fits  between
 spark  plug  leads and distributor.
                                                                               PURPOSE
                                                           Lean air-fuel mixture.
                                                  Improve air-fuel diffusion, lower combustion
                                                  temperatures and increase exhaust gas oxi-
                                                  dation.
Optimize air-fuel mixing.

Enhance combustion ignition.

Recirculate unburned HC and exhaust gas  from
crankcase for combustion'with lean air-fuel
mixture.
Oxidize unburned HC and CO combustion by-
products in exhaust gas.
                                                 Lean air-fuel mixture at high intake  mani-
                                                 fold vacuum during idle  and  deceleration.
                                                 Condition fuel prior to entering  carbure-
                                                 tor.

                                                 Lean air-fuel mixture
                                                 Decrease pollutants  by use  of  lower  reacti-
                                                 vity, cleaner burning gaseous  fuel.
                                                 Lean air-fuel mixture in  combination with
                                                 blowby control.
                                                 Lean air-fuel mixture  in  combination with ex-
                                                 haust gas recirculation to  reduce  combustion
                                                 temperature and  retarded  timing  to increase
                                                 exhaust gas oxidation.

                                                 Combustion byproduct control  in  exhaust system.
                                                 Oxidize unburned  combustion byproducts in
                                                 the  exhaust system.
                                                 Lean air-fuel mixture  combined with retard-
                                                 ed timing to increase  exhaust gas  oxidation.
                                                           Improve oxidation of combustion byproducts
                                                           and reduce combustion to inhibit NOx for-
                                                           mation.
                                                Pre-condition combustion chamber gases in
                                                preparation for ignition event.
                                                                                                           GROUP
                                                                                                            1.2.1
                                                 1.2.2
1.2.6

1.3.2


2.1


1.1.2



1.2.4



1.4.3


1.2.1


1.4.1

1.2.4



1.2.1
                                                4.0
                                                1.1.1

                                                1.3.1
                                                                                                           1.1.1
                                                                                                           1.3.2
                                                       4-2

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                Table 4-1.    DEVICES  EVALUATED  IN THE  RETROFIT PROGRAM  (CONT)
DEVICE
                         DEVICE TITLE
                                                                            PURPOSE
                                                                                                           GROUP
  96  (1)
     (2)
 100  (1)


 160  (3)


 164


 165





 170  (3)



 172  (1)
175  (2)
     (3)
182

244 (1)


245 (2)
246 (1)
    (2)
259


268



279

282
Catalytic Converter with  Distributor Vacuum
Advance Disconnect:  Catalyst  contained in
canister installed between  exhaust manifold
and muffler, combined with  distributor
vacuum advance disconnect,  and/or air in-
jection by special pump.
               exhaust gas  driven  turbo-
                        Hydrocarbon-base fuel
Turbocharger:
charger.

Closed or Open Blowby Control System with
Filter: Filtered, volumetric-controlled
blowby gas reclrculation.
Exhaust Gas Filter:  Two-stage exhaust gas
filter with combined muffler function.

Exhaust Gas Afterbumer/Recirculation with
Blowby and Fuel Evaporation Recirculation:
Combined exhaust gas afterburning and re-
circulation, with crankcase blowby and fuel
evaporation.

Closed Blowby Control System:  Closed blowby
gas recirculation through carburetor air
cleaner and intake manifold combination.

Intake Manifold Modification:  Truncated
conical nozzles inserted between intake port
and intake manifold.

Ignition Timing Modification with Lean Idle
Adjustment:  Electronically controlled igni-
tion spark retardation by sequenced regula-
tion of the distributor ignition signal and
the vacuum advance disconnect, combined with
lean idle air-fuel mixture adjustment.

Fuel and Oil Additives:
and oil additive.

Rich Thermal Reactor:  Exhaust manifold re-
placement providing thermal insulated chamber
and air injection.

Variable Camshaft Timing:  Cam timing gear
replacement automatically varies valve timing
from advance at idle and low rpm to retard at
high speeds.

Speed-Controlled Exhaust Gas Recirculation
with Vacuum Advance Disconnect:  Exhaust gas
recirculation through intake manifold adapter
controlled by speed-sensitive solenoid valve
which also disconnects distributor vacuum
advance during low speed modes.

Photocell-Controlled Ignition System:  Ignition
spark modification by photo-cell controlled
ignition system.
Capacitive Discharge Ignition:  Ignition spark
modification by high-voltage capacitor dis-
charge to ignition coil primary, operating
in series to the distributor and coil.

Fuel Conditioner:
electrical field.

LP Gas Injection:  Propane injection to car-
buretor air intake during acceleration and
engine load conditions,  based on intake mani-
fold vacuum.
                   Intake  fuel routing through
                                                  Oxidize unburned combustion byproducts by
                                                  catalyst action and higher exhaust tem-
                                                  perature.  Reduce NOx by reduced peak
                                                  cycle  combustion temperature.
Improve fuel oxidation during low intake
vacuum by forced air injection to carburetor.
Recirculate blowby gas from crankcase to
intake manifold for combustion,  without
Impurities.
Incomplete data precludes full determination
of purpose; however, one application appears
to be particulate control.
Control all three major sources  of vehicle
emissions.
                                                 To recirculate blowby gas from crankcase  to
                                                 intake manifold for combustion.

                                                 Equalize air-fuel mixture distribution.
                                                 Spark retardation at idle and speeds  below
                                                 35 mph in combination with lean air-fuel
                                                 mixture.
Reduce engine deposits and fuel consump-
tion and increase power.

Oxidize unburned combustion byproducts  in
exhaust manifold.


Provide exhaust gas recirculation.
                                                 Lower combustion temperature combined with
                                                 higher temperature exhaust.
                                                 Increase spark duration and eliminate
                                                 mechanical distributor breaker points.

                                                 Modify firing voltage across the spark
                                                 plugs.
                                                 Condition fuel prior to entering carburetor.

                                                 Addition of lower reactivity, cleaner burn-
                                                 ing fuel.
1.1.1






1.2.5


2.2


1.1.4


4.0





2.1



1.2.3



1.3.1






1.4.2


1.1.2



1.2.2




1.2.2






1.3.2



1.3.2




1.4.3

1.4.2
                                                     4-3

-------
                  Table 4-1.    DEVICES  EVALUATED  IN THE  RETROFIT PROGRAM  (CONT)
 DEVICE
                         DEVICE TITLE
                                                                            PURPOSE
                                                                                                            GROUP
 288 (2)

 292 (1)


 294 (1)

 295 (2)


 296




 308


 315




 317





 322 (1)


 325



 384



 401


 408





 418  (1)


425


427
 Carburetor Main Discharge Nozzle Modification:
 Air  jet added to main circuit nozzle outlet.

 Catalytic Converter:  Platinum catalyst de-
 vice  installed in exhaust pipe.
 Exhaust Gas Recirculation with Carburetor
 Modification: (4)
 Carburetor with Variable Venturi:
 Replacement carburetor incorporating variable
 venturi and fuel nozzle.
 Ignition Timing and Spark Modification:
 Electronically controlled spark retardation
 by delaying distributor breaker point pulse
 to coil, combined with longer spark duration,
 up to mid-rpm range.
 Exhaust Gas Afterburner:  High voltage con-
 tinous-spark chamber ignites exhaust gas up-
 stream of muffler in exhaust system.
 Closed Blowby Control System:  Crankcase
 blowby recirculation through intake manifold
 adapter controlled by accelerator linkage,
 with air-fuel diffusion fans located in
 adapter ports.
 Carburetor Modification with Vacuum Advance
 Disconnect:  Combination air-fuel bypass from
 carburetor to intake manifold, based on in-
 take vacuum and valve metered flow, combined
with vacuum advance disconnect during accelera-
 tion.
Exhaust Gas Backpressure Valve:  Backpressure
 flapper valve installed on end of exhaust
pipe.
Air-Vapor Bleed to Intake Manifold:  Water-
alcohol-air-vapor bleed to intake manifold
 through adapter plate with air bleed during
 idle and crankcase blowby recirculation.

Air-Fuel Mixture Diffuser:   Two-layer,  coni-
 cal wire screen air-fuel diffuser.
Air-Vapor Bleed to Intake Manifold:  Metered
water-alcohol-air vapor bleed to intake mani-
fold from container.
Exhaust Gas and Blowby Recirculation with  In-
take Vacuum Control and Turbulent Mixing:
Exhaust gas recirculation combined with crank-
case blowby recirculation to intake manifold
with vacuum actuated valving and turbulent
mixing.
Air Bleed to Intake Manifold:  Air bleed to
intake manifold through crankcase blowby re-
circulation line.
Exhaust Gas Afterburner:  Exhaust gas after-
burner operating with rich air-fuel ratio
and air injection.
Closed or Open Blowby Control System with
Filter:  Closed- or open-system crankcase  blow-
by recirculation to intake manifold with blow-
by filtering.
                                                  Enhance  air-fuel mixture diffusion.

                                                  Oxidize  emission byproducts of combustion
                                                  in the exhaust  system.
                                                  Optimize air-fuel mixing combined with
                                                  lower combustion temperatures.
                                                  Optimize air-fuel ratio and diffusion.
                                                  Enhance  fuel combustion and increase ex-
                                                  haust  gas  temperature.
                                                  Oxidize unburned byproducts of combustion
                                                  in exhaust  system.
                                                  Mixing  of  blowby gases prior to entering
                                                  intake  manifold.
                                                  Reduce  combustion  temperature and increase
                                                  exhaust  gas  temperature for improved oxida-
                                                  tion  of  unburned combustion byproducts.
                                                  Apply  backpressure on the exhaust system.
                                                  Leaner air-fuel mixture.
                                                  Improve air-fuel mixing and conditioning
                                                  for combustion.
                                                  Leaner air-fuel mixture.
                                                 Blowby control and lower combustion
                                                 temperature.
                                                 Lean air-fuel mixture.
                                                 Oxidize unburned byproducts of combustion.
                                                             Recirculate  filtered blowby gases for com-
                                                             bustion.
1.2.4

1.1.1

1.2.2

1.2.4


1.3.2




1.1.3


2.1




1.2.4





1.1.5


1.2.1




1.2.3



1.2.1


4.0





1.2.1


1.1.3


2.1/2.2
                                                        4-4

-------
Table 4-1.  DEVICES EVALUATED IN THE RETROFIT PROGRAM (CONCL)
DEVICE
430

433


440


457 (1)

458 (1)


459 (1)
(3)



460 (1)
(3)

461 (1)




462 (1)



463 (1)


464 (1)




465 (1)
466 (1)
(3)

467

468



469 (1)




DEVICE TITLE
Induction Modification: Conical screen insert
between carburetor and intake manifold.
Air-Vapor Bleed to Intake Manifold: Exhaust
gas afterburner operating with lean air-fuel
ratio and air injection.
Air-Fuel Mixture Deflection Plate: Shaped de-
flection plate insert between carburetor and
intake manifold.
Water Injection: Water-alcohol-air vapor in-
jection to intake manifold.
Air Bleed to Intake Manifold: Air-vapor in-
jection to intake manifold through positive
ventilation line.
LPG Conversion with Deceleration Unit:
Liquified petroleum gas (LPG) carburetor
conversion with deceleration throttle control
device.

Compressed Natural Gas Dual-Fuel Conversion:
Dual-fuel conversion enabling use of compres-
sed natural gas or gasoline.
LPG Conversion with Exhaust Reactor Pulse Air
Injection and Exhaust Gas Recirculation :
Liquified petroleum gas conversion with
exhaust reactor, exhaust gas recycle, and
pulse air injection to reactor.
Air Bleed to Intake and Exhaust Manifolds :
Air bleed to intake manifold through crankcase
blowby recirculation line, with exhaust .
dilution by air bleed.
Rich Thermal Reactor with Exhaust Gas Recircu-
lation and Spark Retard: Replacement exhaust
manifold.
Methanol Fuel Conversion with Catalytic Con-
verter: Engine conversion for operation on
methanol fuel, combined with exhaust gas
oxidation by catalytic reaction, plus
exhaust gas recirculation option.
Fuel Additive: Bycosin fuel additive.
LPG-Gasoline Dual-Fuel Conversion: Dual-fuel
conversion enabling use of liquified petroleum
gas or gasoline.
Fuel Evaporation Control System: Fuel evapora-
tion control by carbon canister storage.
Lean Thermal Reactor with Exhaust Gas Recircula-
tion: Reactor air supplied by lean air fuel
mixture with recirculation of oxidized exhaust
gas.
Rich Thermal Reactor with Exhaust Gas Recircula-
lation and Particulate Control: Replacement
exhaust manifold (thermal reactor) with re-
circulation of oxidized exhaust gas and particu-
late trapping.
PURPOSE
To diffuse air-fuel mixture.

Oxidize unbumed byproducts of combustion.


To diffuse air-fuel mixture.


Oxidize unburned byproducts of combustion.

Oxidize unburned byproducts of combustion.


Decrease pollutants by use of lower reactivity,
cleaner burning LPG; combined with delayed
throttle closure during deceleration, to
enhance combustion of residual fuel in the
intake manifold.
Decrease pollutants by use of lower reactivity,
cleaner burning natural gas during high-
emission-potential driving modes.
Decrease pollutants by use of lower reactivity,
cleaner burning gaseous fuel combined with
oxidation of combustion byproduct.


Lean air-fuel mixture.



Oxidize combustion byproducts in the exhaust
system, while lowering combustion temperature
to inhibit NOx.
Decrease pollutants by use of lower reactiv-
ity, cleaner burning fuel and catalytic
oxidation of exhaust gas.


To enhance combustion efficiency.
Decrease pollutants by use of lower reactiv-
ity, cleaner burning natural gas during high-
emission-potential driving modes.
Control fuel evaporation from fuel tank and
carburetor.
Oxidize combustion byproducts and provide
lower combustion temperatures, plus particulate
control.

Oxidize combustion byproducts and provide
lower combustion temperatures, plus particu-
late control.


GROUP
1.2.3

1.2,1


1.2.3 '


1.4.2

1.2.1


1.4.1




1.4.1


1.4.1




1.2.1



1.1.2


1.4.1




1.4.2
1.4.1


3.0

1.1.2



4.0




(1) Previously tested by EPA.
(2) Tested in retrofit program.
(3) Accredited for use in California. In the case of Device 459, accreditation does not refer
to the deceleration control unit.
(4) System description data not available.
                          4-5

-------
Table  4-2.  AVERAGE PERCENTAGE  EXHAUST  EMISSION  REDUCTION BY TEST PROCEDURE
                   FOR DEVICES EVALUATED  IN RETROFIT PROGRAM
     NOTE:  THE RELIABILITY OF THE DATA SHOWN DEPENDS ON THE TYPE OF TEST PROCEDURE AND NUMBER OF TESTS.


T F S
TYP















w
>
u
^
S
p
o
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u
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a,
H
01
ui
H
j
2
LU
Q
UJ
[H
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r-.
o->

























w
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J
§2
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6



ITH-



11EVIC1



DESCRIPTION
Retrofit Program Test Data
(Up to 18 Tests for Each Device) :
1
2

3

4

1
96

175

246

Air Bleed to Intake Manifold
Catalytic Converter with Distributor
Vacuum Advance Disconnect
Ignition Timing Modification with Lean
Idle Adjustment
Speed-Controlled Exhaust Gas Recircula-
tion with Vacuum Advance Disconnect
Retrofit Program Test Data
(Up to 3 Tests for Each Device):
5

6

7
8


9
10

11
10

33

42
69


245
288

295
Throttle-Controlled Exhaust Gas Recircu-
lation with Vacuum Advance Disconnect
Carburetor Modification, Main Jet Dif-
ferential Pressure
Air Bleed to Intake Manifold
Electronic-Controlled Vacuum Advance
Disconnect and Carburetor Lean Idle
Modification
Variable Camshaft Timing
Carburetor Main Discharge Nozzle
Modification
Carburetor with Variable Venturi

Developer and EPA Supplied Data:

12
13

14
15
16
17
18
19

20
21

22

23
24

23
24

52
95
' 100'
172
292
294

418
460

462

465
466

Electronic Ignition Unit
Heavy Duty Positive Crankcase Control
Valve with Air Bleed
LPG Conversion
Ignition Spark Modification
Turbocharger
Intake. Manifold Modification
Catalytic Converter
Exhaust Gas Recirculation with
Carburetor Modification
Air Bleed to Intake Manifold
Compressed Natural Gas Dual-Fuel
Conversion
Air Bleed to Intake and Exhaust
Manifolds
Fuel Additive
LPG-Gasoline Dual-Fuel Conversion
No Baseline Given for the Following Devices: (12)
25


26
27


28

29

30

1



93


459
461


463

464

468

469



Catalytic Converter with Exhaust Gas
Recirculation, Spark Modification, and
Lean Idle Mixture
LPG Conversion with Deceleration Unit
LPG Conversion with Exhaust Reactor
Pulse Air Injection and Exhaust Gas
Recirculation
Rich Thermal Reactor with Exhaust Gas
Recirculation and Spark Retard
Methanol Fuel Conversion with Catalytic
Converter
Lean Thermal Reactor with Exhaust Gas
Recirculation
Rich Thermal Reactor with Exhaust Gas
Recirculation and Particulate Control




nATA
1JA1A.
SOURCE (3


R
R

R

R



R

R

R
R


R
R

R



E
E

E
E
E
E
E
E

E
E

E

E
E

E


E
E


E

E

D

E





NO.
f)V
Uc
TESTS


18
17

10

15



2

2

2
3


• 1
2

1



1
(4)

18
1
1
1
1
1

(5)
1

(6)

1
6

6


1
1


3

6

5

2



AVERAGE PERCENTAGE
EMISSION
REDUCTION(l)
HC


21.0
68.4

19.2

12.1



36.7

32.9

23.2
32.4


-35.9
4.1

-36.9



2.9
3.9

81.1
-26.7
14.0
-15.0
21.2
-78.9

8.2
0.0

24.6

12.3
19.0

(7)


(7)
(7)


(7)

50.0

(7)

80.0



CO


57.8
62.6

46.3

30.9



28.7

45.8

45.3
29.2


-26.9
36.9

20.0



-16.3
12.6

85.2
-17.4
12.0
0.0
-15.4
10.4

39.4
-19.0

12.6

9.9
70.0

(7)


(7)
(7)


(7)

16.0

(7)

44.0



NOX


-4.8
47.8

37.2

47.6



53.6

-43.4

2.6
24.4


20.9
-18.7

25.4



-56.0
7.4

64.9
-31.3
8.0
27.0
41.0
30.0

1.9
-64.0

-30.0

8.2
29.0

(7)


(7)
(7)


(7)

96.0

(7)

65.0




FUEL
CONSUMPTION
pyppTT'UTAr'Tr
r HK.UC.W lALiL
CHANGE(2)


. 4
-1

-10

7



0.5

13

• 7
0


-10
' -6

-10



No data
available





























4
V





























No data
available

                                        4-6

-------
Table  4-2.  AVERAGE PERCENTAGE  EXHAUST  EMISSION  REDUCTION BY TEST  PROCEDURE
                   FOR DEVICES EVALUATED  IN RETROFIT PROGRAM (CONCL)
     NOTE:  THE RELIABILITY OF THE DATA SHOWN DEPENDS ON THE TYPE OF TEST PROCEDURE AND NUMBER OF TESTS.



TYPE






H
<
en
Q
O
u

1
X
1
r*
u

I









H

H

X
Id
Q
S
^


Q [14
E~* H*
W C/3






if
9
1 '






ITEM



DEVICE



DESCRIPTION
7-Cycle 7-Mode Cold Start Test Procedure:
1

2

3
4
5
6
7
8
9
10
11
12
13
14
15
36

57

, 59
62
164
182
244
315
317
322
384
401
425
430
458
Fuel Conditioning by Exposure to
Electromagnetic Field
Air Bleed with Exhaust Gas Recirculation
and Vacuum Advance Disconnect
Three-Stage Exhaust Gas Control System
Catalytic Converter
Exhaust Gas Filter
Fuel and Oil Additives
Rich Thermal Reactor


nATA
UAiA
SOURCE (3)

E

D

D
E
D
D
D
Closed Blowby Control System D
Carb Mod with Vac Adv Disconnect
Exhaust Gas Backpressure Valve
Air-Fuel Mixture Diffuser
Air-Vapor Bleed to Intake Manifold
Exhaust Gas Afterburner
Induction Modification
Air Bleed to Intake Manifold
No Baseline Given for the Following Devices: (12)
16
17 :

18
19

22
31

56
160

Electronic Fuel Injection
Thermal Reaction by Turbine Blower Air
Injection
Crankcase Blowby and Idle Air Bleed Mod
Closed or Open Blowby Control System
with Filter
7-Cycle 7-Mode Hot Start Test:
1
2
3
4
5

6
170
279
296
325
427

433

Closed Blowby Control System
Fuel Conditioner
Ignition Timing and Spark Modification
Air-Vapor Bleed to Intake Manifold
Closed or Open Blowby Control System
with Filter
Air-Vapor Bleed to Intake Manifold

No Baseline Given for the Following Device: (12)
7


165


Steady State
1
2
308
457
Exhaust Gas Afterburner /Recirculation
with Blowby and Fuel Evaporation
Recirculation

Exhaust Gas Afterburner
Water Injection
No Emission Data Provided by the Developer for the
Following Devices :
1
2
3
4


5
259
268
282
408


440
Photocell-Controlled Ignition System
Capacitlve Discharge Ignition
LP Gas Injection
Exhaust Gas and Blowby Recirculation
with Intake Vacuum Control and
Turbulent Mixing
Air-Fuel Mixture Deflection Plate
No Emission Evaluation was Made on the Following
Device:
6
467

Fuel Evaporation Control System
D
E
D
D
D
D
E

E
D

D
D


D
D
D
D
D

D


D



D
E '


D
D
D
D


D


(7)


NO.
f\rf
Ur
TESTS

(8)

1

1
1
1
(9)
(7)
1
3
1
1
1
1(10)
2
(ID

1
6

3
1


1
1
1
7
2

7


1



3(13)
(13)


(7)
(7)
(7)
(7)


(7)


(7)
AVERAGE PERCENTAGE
EMISSION
REDUCTION(l)
HC

-12.5

55.8

32.0
44.0
10.0
26.2
83.0
28.3
32.0
-71.3
40.2
25.0
97.0
34.0
-3.7

(7)
(7)

(7)
(7)


10.0
3.4
8.0
29.7
5.5

29.7


(7)



-17.0
0.0


(7)
(7)
(7)
(7)


(7)


(7)
CO

-0.4

52.3

18.3
14.5
2.0
30.5
67.0
28.0
22.0
6.9
19.6
34.1
97.0
9.5
7.0

(7)
(7)

(7)
(7)


-31.0
24.5
4.0
32.1
48.6

32.1


(7)



-6.3
0.0


(7)
(7)
(7)
(7)


(7)


(7)
NOX

(7)

46.6

11.0
7.0
0.1
24.0
(7)
(7)
35.0
-13.0
29.4
-31.0
(7)
36.5
-8.1

(7)
(7)

(7)
(7)'


47.0
4.3
-4.0
10.0
0.5

10.0


(7)



9.0
75(15)


(7)
(7)
(7)
(7)


(7)


(7)

FUEL
CONSUMPTION
PERCENTAGE
CHANGE(2)

No data
available

'








\






























'





\
No d















































t
ata
available
(1) Negative signs indicate an emission increase. (7) Unknown.
(2) Measured during 1972 Federal Test Procedure for (6) 1 baseline and 11 device tests for HC and CO only.
exhaust emissions. Negative signs indicate less (9) 4 tests for HC and CO; 1 test for NOx.
miles per gallon. (10) HC and CO measured only.
(3) Data Source: (11) 1 baseline and 2 device tests on 1 car.
R = Retrofit Test Program (12) See Volume II for emission levels with devices
D = Developer Supplied Data installed.
E = Environmental Protection Agency (13) Different steady state speeds.
(4) 6 baseline and 5 device tests for HC and CO; (14) EPA Interim 9-Cycle, 7-Mode CVS Emission Test
3 baseline and 4 device tests for NOx. Procedure (refer to Volume II, Reference 16).
(5) 16 baseline tests and 11 device tests on 3 cars. (15) NOx reduction reported for water-to-fuel ratio
(6) 10 baseline and 9 device tests for HC and CO, and of 0.9:1. No appreciable effect reported for
6 baseline and 6 device tests for NOx, on 2 cars. HC or CO.
                                         4-7

-------
Table  4-3.  AVERAGE PERCENTAGE EXHAUST EMISSION REDUCTION OF DEVICES EVALUATED
           IN RETROFIT PROGRAM - LISTED BY DEVICE CLASSIFICATION (1)
        NOTE:  THE RELIABILITY OF THE DATA SHOWN DEPENDS ON THE TYPE OF TEST PROCEDURE AND NUMBER OF TESTS.
DEVICE
NO.
.*
DESCRIPTION
AVERAGE EMISSION
REDUCTION %
HC
CO
NOx
NO. OF
TESTS
DATA
SOURCE (2)
TEST
TYPE
GROUP 1 EXHAUST EMISSION CONTROL SYSTEMS


62
93


96

292

31

244
463

468


308
425

164

322


1
42
57
325
401
418
433
458
462


10

245
246

294

Type 1.1 Exhaust Gas Control Systems:
1.1.1 Catalytic Converter
Catalytic Converter
Catalytic Converter with Exhaust Gas
Recirculatlon, Spark Modification, and
Lean Idle Mixture
Catalytic Converter with Distributor
Vacuum Advance Disconnect
Catalytic Converter
1.1.2 Thermal Reactor
Thermal Reaction by Turbine Blower Air
Injection
Rich Thermal Reactor
Rich Thermal Reactor with Exhaust Gas
Recirculation and Spark Retard
Lean Thermal Reactor with Exhaust
Gas Recirculation
1.1.3 Exhaust Gas Afterburner
Exhaust Gas Afterburner
Exhaust Gas Afterburner
1.1.4 Exhaust Gas Filter
Exhaust Gas Filter
1.1.5 Exhaust Gas Backpressure
Exhaust Gas Backpressure Valve
Type 1.2 Induction Control Systems:
1.2.1 Air Bleed to Intake Manifold
Air Bleed to Intake Manifold
Air Bleed to Intake Manifold
Air Bleed with Exhaust Gas Recirculation
and Vacuum Advance Disconnect
Air-Vapor Bleed to Intake Manifold
Air Bleed to Intake Manifold
Air-Vapor Bleed to Intake Manifold
Air Bleed to Intake Manifold
Air Bleed to Intake and Exhaust
Manifolds
1.2.2 Exhaust Gas Recirculation
Throttle-Controlled Exhaust Gas Recir-
culation with Vacuum Advance Disconnect
Variable Camshaft Timing
Speed-Controlled Exhaust Gas Recircu-
lation with Vacuum Advance Disconnect
Exhaust Gas Recirculation with
Carburetor Modification


44.0
(9)


68.4

21.2

(9)

83.0
(9)

(9)


-17.0
97.0

10.0

-71.3


21.0
23.2
55.8
90 7
t.y • /
25.0
8.2
29.7
-3.7
24.6


36.7

-35.9
12.1

-78.9



14.5
(9)


62.6

-15.4

(9)

67.0
(9)

(9)


-6.3
97.0

2.0

6.9


57.8
45.3
52.3
1? 1
J^ . JL
34.1
39.4
32.1
7.0
12.6


28.7

-26.9
30.9

10.4



7.0
(9)


47.8

41.0

(9)

(10)
(9)

(9)


9.0
(10)

0.1

-13.0


-4.8
2.6
46.6
10 0
-31.0
1.9
10.0
-8.1
-30.0


53.6

20.9
47.6

30.0



1
6


17

1

6

(10)
3

5


3 .
1(11)

1

1


18
2
1
7
1
(12)
7
(13)
(14)


2

1
15

1



E
E


R

E

D

D
E

D


D
D

D

E


R
R
D

D
E
D
E
E


R

R
R

E



(3)
(4)


(4)

(4)

(3)

(3)
(4)

(4)


(6)
(3)

(3)

(3)


(4)
(4)
(3)
(1 \
\l )
(3)
(4)
(7)
(3)
(4)


(4)

(4)
(4)

(4)

                                          4-8

-------
Table  4-3.  AVERAGE PERCENTAGE EXHAUST EMISSION REDUCTION OF DEVICES EVALUATED
           IN RETROFIT PROGRAM - LISTED BY DEVICE  CLASSIFICATION (1)  (CONT)
     NOTEi   THE RELIABILITY OF THE DATA SHOWN DEPENDS ON THE TYPE OF TEST PROCEDURE AND NUMBER OF TESTS.
DEVICE
NO.

172
384
430
440

33

56

288

295
317


100

22


69


175


23
95
259
268
296


52
459
460

461


464

466
DESCRIPTION
1.2.3 Intake Manifold Modification
Intake Manifold Modification
Air-Fuel Mixture Diffuser
Induction Modification
Air-Fuel Mixture Deflection Plate
1.2.4 Carburetor Modification
Carburetor Modification, Main Jet
Differential Pressure
Crankcase Blowby and Idle Air Bleed
Modification
Carburetor Main Discharge Nozzle
Modification
Carburetor with Variable Venturi
Carburetor Modification with Vacuum
Advance Disconnect
1.2.5 Turbocharger
Turbocharger
1.2.6 Fuel. Injection
Electronic Fuel Injection
Type 1.3 Ignition Control Systems:
1.3.1 Ignition Timing Modification
Electronic-Controlled Vacuum Advance
Disconnect and Carburetor Lean Idle
Modification
Ignition Timing Modification with Lean
Idle Adjustment
1.3.2 Ignition Spark Modification
Electronic Ignition Unit
Ignition Spark Modification
Photocell-Controlled Ignition System
Capacitive Discharge Ignition
Ignition Timing and Spark Modification
Type 1.4 Fuel Modification:
1.4.1 Alternative Fuel Conversion
LPG Conversion
LPG Conversion with Deceleration Unit
Compressed Natural Gas Dual-Fuel
Conversion
LPG Conversion with Exhaust Reactor Pulse
Air Injection and Exhaust Gas Recir-
culatlon
Methanol Fuel Conversion with Catalytic
Converter
LPG-Gasollne Dual-Fuel Conversion
AVERAGE EMISSION
REDUCTION %
HC

-15.0
40.2
34.0
(10)

32.9

(9)

4.1

-36.9
32.0


14.0

(9)


32.4


19.2


2.9
-26.7
(10)
(10)
8.0


81.1
(9)
0.0

(9)


(9)

19.0
CO

0.0
19.6
9.5
(10)

45.8

(9)

36.9

20.0
22.0


12.0

(9)


29.2


46.3


-16.3
-17 .4
(10)
(10)
4.0


NOx

27.0
29.4
36.5
(10)

-43.4

(9)

-18.7

25.4
35.0


8.0

(9)


24.4


37.2


-56.0
-31.3
(10)
(10)
-4.0


85.2 j 64.9
(9)
-19.0

(9)
| -64.0

(9) (9)


(9)

70.0


(9)

29.0
NO. OF
TESTS

1
1
2
(8)

2

3

2

1
3


1

1


3


10


1
1
(8)
(8)
1


18
1
1

1


6

6
DATA
SOURCE (2)

E
D
D
D

R

D

R

R
D


E

E


R


R


E
E
D
D
D


E
E
E

E


E

E
TEST
TYPE

(4)
(3)
(3)
(8)

(4)

(3)

(4)

(4)
(3)


(4)

(3)


(4)


(4)


(4)
(4)
(8)
(8)
(7)


(4)
(4)
(4)

(4)


(4)

(4)
                                          4-9

-------
Table 4-3.   AVERAGE  PERCENTAGE  EXHAUST EMISSION  REDUCTION OF DEVICES  EVALUATED
              IN  RETROFIT  PROGRAM - LISTED BY  DEVICE CLASSIFICATION (1)  (CONCL)
        NOTE:   THE RELIABILITY OF THE DATA  SHOWN DEPENDS ON THE TYPE OF TEST PROCEDURE AND NUMBER OF TESTS.
    DEVICE
      NO.
                        DESCRIPTION
                                                         AVERAGE  EMISSION
                                                            REDUCTION %
                                                        HC
                                                                CO
                                                                        NOx
                                                                    NO.  OF
                                                                    TESTS
                                   DATA
                                   SOURCE(2)
                                      TEST
                                      TYPE
     182

     282

     457

     465



      36


     279
1.4.2  Fuel Additive

Fuel and Oil Additives

LP Gas Injection
Water Injection

Fuel Additive
1.4.3  Fuel Conditioner

Fuel Conditioning  by  Exposure'to
Electromagnetic Field

Fuel Conditioner
 26.2

 (10)
  0.0
 12.3


-12.5

  3.4
30.5
 (10)
 0.0
 9.9


-0.4

24.5
 24.0
 (10)
75(18)
 _8.2


 (8)

 4.3
(15)

(8)

(6)
 1


(16)


 1
(3)

(8)

(6)
(4)



(3)


(7)
                                   GROUP  2 CRANKCASE EMISSION CONTROL  SYSTEMS
            Type 2.1 Closed System:

      24     Heavy Duty Positive Crankcase Control
            Valve with Air Bleed

     170     Closed Blowby Control System
          I
     315     Closed Blowby Control System

            Type 2.2  Open System:

     160     Closed or Open Blowby Control System
            with Filter

     427     Closed or Open Blowby Control System
            with Filter
                                            3.9

                                           10.0

                                           28.3
                                            (9)

                                            5.5
         12.6

         -31.0
         28.0
           (9)

          48.6
          7.4

         47.0
         (9)
          (9)

          0.5
          (17)

           1
           1
                    (4)

                    (7)
                    (3)
                              (3)


                              (7)
                               .   GROUP  3  EVAPORATIVE EMISSION CONTROL  SYSTEMS
     467
            Fuel Evaporation Control  System
                                           (10)
          (10)
         (10)
                                                                     (8)
                            (10)
                                                (8)
                                   GROUP 4 EMISSION CONTROL COMBINATIONS
      59
     165


     408


     469
Three-Stage Exhaust Gas Control System
Exhaust Gas Afterburner/Recirculation
with Blowby and  Fuel  Evaporation
Recirculation
Exhaust Gas and  Blowby Recirculation
with Intake Vacuum Control and
Turbulent Mixing
Rich Thermal Reactor  with Exhaust Gas
Recirculation and  Particulate Control
 32.0
  (9)


 (10)


 80.0
18.3
 (9)


(10)


44.0
 11.0

  (9)


 (10)


 65.0
 1
 1



(8)
(3)

(7)


(8)


(5)
   (1) Classification of retrofit system is shown in   (10)
         Table 1-1.   Refer to  Volume II for emission   (11)
         levels with and without device installed on   (12)
         test car.                                    (13)
   (2) Data Source:                                    (14)
         R = Retrofit Test Program
         D = Developer Supplied Data
         E = Environmental Protection Agency           (15)
   (3) 7-cycle, 7-mode cold-start test procedure.      (16)
   (4) 1972 Federal Test Procedure.
   (5) EPA 9-Cycle,  7-Mode CVS Test Procedure.         (17)
   (6) Different steady state  speeds.
   (7) 7-cycle, 7-mode hot-start test procedure.       (18)
   (8) No test.
   (9) No baseline data reported by test source.
                                              Unknown.
                                              HC and CO measured only.
                                              16 baseline tests and 11  device  tests on 3 cars.
                                              1 baseline and 2 device tests  on 1  car.
                                              10 baseline and 9 device  tests for  HC and CO,
                                                and 6 baseline and 6 device  tests for NOx,
                                                on 2 cars.
                                              4 tests for HC and CO; 1  teat  for NOx.
                                              1 baseline test and 11 device  tests for HC and
                                                CO only.
                                              6 baseline and 5 device tests  for HC and CO;
                                                3 baseline and 4 device tests  for NOx.
                                              NOx reduction reported for water-to-fuel ratio
                                                of 0.9:1.  No appreciable effect  reported for
                                                HC or CO.
                                                   4-10

-------
     c.   Air Bleed to Intake Manifold;  Leaner air-fuel mixture is produced,
          decreasing CO, and to a lesser extent, HC, by oxidation.

     d.   Ignition Timing Modification;  Ignition timing is retarded, by disconnect-
          ing the distributor vacuum advance at low speeds, to lower combustion
          temperature and NOx, with some post-combustion oxidation of HC.

4.1.1  Exhaust Emission Control Systems Group

To develop the data necessary to establish a reasonable level of confidence in the
effectiveness indicated for devices in this group, a representative device from
each of the four above types was selected for emission and driveability testing on
test vehicle fleets located in Anaheim, California, and in Taylor, Michigan.

4.1.1.1  Percentage Exhaust Emission Reduction

The emission level of the car prior to device installation was referred to as the
"baseline emissions," whereas the emission level with the device installed was the
"retrofit emissions."  The effectiveness of the device in controlling the car's
emissions was then calculated for each pollutant in terms of percentage reduction.
The formula used for this calculation is:

                  „  ,         Baseline Emissions - Retrofit Emissions  „ i nn
       Percentage Reduction =	—	•—	;	  x iUU
                                        Baseline Emissions

Table 4-4 shows the percentage exhaust emission reductions obtained for the devices
in these tests.

4.1.1.2  Statistical Analysis of Representative Exhaust Emission Control Device
         Test Results

Two kinds of statistical testing were used on the emission reduction data of devices
tested in the retrofit program.  One statistical test determined whether the
replicate results and the results from the two cities could be combined.  This was
accomplished using Welch's approximate t solution for the Fisher-Behrens problem.
The Fisher-Behrens problem is the testing of the hypothesis that the means of two
normal populations are equal regardless of the size of their respective variances
based on two samples, one drawn from each population.  A brief description and a
sample calculation of Welch's approximate solution of the Fisher-Behrens problem is
presented in Volume III, Appendix H.(1)

The second statistical test considered whether the percentage emission reduction was
different than zero for results of a given location or for location data combinations.
This test used a normal student t  test.  Two sided 90 percent confidence limits were
calculated for the mean percentage emission reductions.
(1)welch, B. L., Biometrika 34, 28-35, January 1947.
                                        4-11

-------
Table 4-4.  PERCENTAGE EXHAUST EMISSION REDUCTION OF DEVICES  TESTED
                        IN RETROFIT PROGRAM
CAR NO. AND
LOCATION (1) MAKE AND CID
Device 1: Air Bleed to Intake
Manifold
Anaheim
1 65 Chev 194
2 65 Ford 289
3 65 Ply 318
4 65 Chev 327
5 65 Ford 390
6 61 Chev 283
17 65 Ford 390
18 61 Chev 283
19 65 VW 92
Taylor
8 65 Ford 289
9 65 Ply 318
10 65 Chev 327
11 65 Ford 390
12 61 Chev 283
16 65 Chev 327
20 65 VW 92
Device 96: Catalytic Converter
with Vacuum Advance Disconnect
Anaheim
1 65 Chev 194
2 65 Ford 289
3 65 Ply 318
4 65 Chev 327
5 " 65 Ford 390
6 61 Chev 283
Taylor
8 65 Ford 289
9 65 Ply 318
10 65 Chev 327
11 65 Ford 390
12 61 Chev 283
Device 246: Speed-Controlled
Exhaust Gas Recirculation with
Vacuum Advance Disconnect
Anaheim
1 65 Chev 194
2 65 Ford 289
3 65 Ply 318
4 65 Chev 327
17 65 Ford 390
18 61 Chev 283
19 65 VW 92
TEST 1
HC



17.7
30.5
-8.2
4.8
20.8
(3)


46.4

41.0
26.5
-29.0
23.6
46.0

71.2



85.1(4)
92.2(4)
34.1
86.7(4)
40.6
68.1(4)

66.6
85.3
70.8
92.9(4)
86.2(4)




(3)
27.6
-13.7
2.8
0.9
(3)
15.4
CO



-6.3
31.4
60.6
46.4
41.4
36.1


56.9

89.3
79.3
93.1
74.0
50.4

85.5



78.3
95.1
12.1
99.2
24.1
32.9

67.4
83.2
77.6
99.5
95.8




12.4
33.7
32.9
23.4
10.3
-8.3
11.6
NOx



-50.5
-10.6
16.6
14.6
0.0
12.7


12.4

24.9
13.9
-0.3
-28.4
3.6

6.9



76.7
65.0
68.8
38.0
66.3
34.6

51.7
58.1
61.7
57.6
50.0




60.0
37.4
54.5
36.9
58.5
44.5
26.1
TEST 2
HC



(2)









3.1
6.9
2.8
51.6
1.9





51.6(4)
75.6(4)
65.9(4)
75.1(4)
38.4
48.7

















CO













77.9
34.7
73.1
63.2
52.6





77.4
63.2
51.2
76.6
26.9
4.1

















NOx













-17.4
24.8
-18.8
-57.5
-33.1





15.7
41.1
30.2
56.6
28.1
11.6

















                                4-12

-------
Table 4-4.  PERCENTAGE EXHAUST EMISSION REDUCTION OF DEVICES TESTED
                     IN RETROFIT PROGRAM (CONT)
CAR NO. AND
LOCATION (1) MAKE AND CID
Taylor
8 65 Ford 289
9 65 Ply 318
10 65 Chev 327
11 65 Ford 390
12 61 Chev 283
20 65 VW 92
Device 175: Ignition Timing
Modification with Lean Idle
Adjustment
Anaheim
1 65 Chev 194
3 65 Ply 318
4 65 Chev 327
5 65 Ford 390
6 61 Chev 283
Taylor
8 65 Ford 289
9 65 Ply 318
10 65 Chev 327
11 65 Ford 390
12 61 Chev 283
16 65 Chev 327
Device 10: Throttle-Controlled
Exhaust Gas Recirculation with
Vacuum Advance Disconnect
Anaheim
4 65 Chev 327
6 61 Chev 283
Device 33: Carburetor Main Jet
Differential Pressure Modifica-
tion
2 65 Ford 289
4 65 Chev 327
Device 42: Air Bleed to In-
take Manifold
4 65 Chev 327
5 65 Ford 390
TEST 1
HC

(3)
8.3
(3)
18.0
9.9
9.4




14.1
33.1
4.8
-21.0
(3)

16.8
26.5
19.0
24.5
33.7
40.0




45.9
27.5



52.7
13.0


-7,6
54.0
CO

(3)
58.4
(3)
31.4
30.1
-26.6




11.4
21.5
8.1
-9.8
(3)

76.5
78.7
61.1
74.7
67.0
73.4




39.0
18.3



62.8
28.7


50.0
40.9
NOx

(3)
47.6
(3)
44.7
40.9
(3)




43.6
43.0
14.9
35.2
(3)

56.6
42.5
56.5
3.0
34.4
42.8




55.5
51.6



-121.6
34.9


-3.1
8.3
TEST 2
HC

-11.1
-5.0
18.3
46.0
40.2
































CO

-4.2
60.8
45.4
72.8
53.4
































NOx

57.7
58.1
55.8
49.3
41.4
































                                 4-13

-------
        Table 4-4.  PERCENTAGE EXHAUST EMISSION REDUCTION OF DEVICES TESTED
                             IN RETROFIT PROGRAM (CONCL)
CAR NO. AND
LOCATION (1) MAKE AND CID
Device 69: Electronic-
Controlled Vacuum Advance
Disconnect and Carburetor Lean
Idle Modification
Anaheim
3 65 Ply 318
4 65 Chev 327
5 65 Ford 390
Device 245: Variable Camshaft
Timing
6 61 Chev 283
Device 288: Carburetor Main
Discharge Nozzle Modification
2 65 Ford 289
6 61 Chev 283
Device 295: Carburetor with
Variable Venturi
5 65 Ford 390
TEST 1
HC


39.2
27.5
30.6

-35.9

6.2
2.0
-36.9
CO


30.1
37.6
20.0

-26.9

38.9
34.8
20.0
NOx


32.1
-5.6
46.7

20.9

-1.8
-35.6
25.4
TEST 2
HC








CO








NOx








(1) Positive percentage denotes emission reduction from baseline and negative percentage
denotes emission increase from baseline.
(2) All blank spaces and columns denote that no tests were performed, except for Note (3).
(3) Measured test data were invalid.
(4) Air pump installed and operating.
Although the absolute magnitude of the percentage reduction is subject to considerable
error due to the small sample size of the retrofit test program, the mean values
still represent the best known estimate of the true values.  The statistical data
provided by this analysis are shown in Table 4-5.  A discussion of the emission
reduction statistical confidence limits is presented in Volume III, paragraph 6.1.

4.1.1.3  Statistical Analysis Conclusions

Figure 4-1 shows the 90 percent confidence limits calculated for the emission
reduction effectiveness of the four representative devices.

Device 96, the catalytic converter with distributor vacuum advance disconnect,
shows a large percentage reduction for all three pollutants.
                                        4-14

-------
Device 175, the ignition timing modification system with lean idle mixture
adjustment (which has been accredited by California for retrofit installation on
1955-65 model year cars), was effective for NOx control, with mean reduction
levels centering on the 37 percent reduction level.  The HC mean reduction level
of this device was also statistically significant.


Since Device 175 is an ignition timing modification with lean carburetor idle
mixture by adjustment, it is not likely that this device controls the overall CO
during a CVS test to a significant degree.  It is known that lean idle mixture will
reduce the overall CO level to some extent, but not to the extent shown in the
Taylor data (an average of 72 percent).  By comparison, the Anaheim data showed a
mean CO reduction of 8 percent.  This CO reduction may be more representative for
this device.


Table  4-5.  MEAN  PERCENTAGE EMISSION  REDUCTION AND 90  PERCENT  CONFIDENCE  INTERVALS
                    FOR EXHAUST EMISSION CONTROL  RETROFIT SYSTEMS TESTED AT
                      ANAHEIM,  CALIFORNIA AND  TAYLOR,  MICHIGAN (1)  (2)
Hydrocarbon Reduction (%)
Test Data
Combination
Mean
(n)
90%
Confidence
Limits
Carbon Monoxide Reduction (7.)
Test Data(3)
Combination
Mean
(n)
90%
Confidence
Limits
Oxides of Nitrogen Reduction (%)
Test Data(3)
Combination
Mean
(n)
90%
Confidence
Limits
Device 1: AIR BLEED TO INTAKE MANIFOLD
WT2
21.0(17)
10.4 to 31.6
Al
VT2
38.1(7)
70.3(11)
2l'.8 to 54.4
60.4 to 80.2
A1+T1+T2
-4.8(18)
-14.9 to 5.4
Device 96: CATALYTIC CONVERTER WITH VACUUM ADVANCE DISCONNECT
VA2
Tl
63.5(12)
80.4(5)
53.0 to 74.0
69.7 to 91.0
A1+A2
Tl
53.4(12)
84.7(5)
36.5 to 70.4
72.1 to 97.3
VT1
A2
57.1(11)
30.6(6)
50.2 to 64.1
16.9 to 44.2
Device 175: IGNITION TIMING MODIFICATION WITH LEAN IDLE ADJUSTMENT
VT1
19.2(10)
8.9 to 29.3
Al
' Tl
7.8(4)
71.9(6)
-7.6 to 23.1
66.5 to 77.3
A1+T1
37.3(10)
27.5 to 47.0
Device 246: SPEED-CONTROLLED EXHAUST GAS RECIRCULATION AND VACUUM ADVANCE DISCONNECT
VT1+T2
12.1(13)
3.1 to 21.1
T1+T2
Al
43.5(8)
16.6(1)
27.3 to 59.7
5.7 to 27.4
VT1+T2
47.6(15.)
43.1 to 52.1
Negative reductions indicate an emission level increase from baseline
(2)
Confidence intervals calculated from data presented in Table 6-1 (Volume III)
AI = Anaheim Test 1 TI = Taylor Test 1
A2 = Anaheim Test 2 T2 = Taylor Test 2
(4)
A]^+T^+T2 means that Anaheim Test 1, Taylor Tests 1 and 2 reduction data were combined as a single
sample. See Volume III, Appendix H, for explanation of test data combinations as determined by
Welch's approximate t solution of the Fisher-Behrens problem. (X) indicates total number of tests.
                                         4-15

-------
Device 246:
Device 175:
Device 1: Device 96: Ignition Timing
. Air Bleed to Catalytic Converter with Modification with Lean
Intake Manifold Vacuum Advance Disconnect Idle Adjustment
l ii ii i
100 r C0

g SO
±J
U
1 «o
cC
O
« ' 40
B
- I'ercent En
N>
0 0
-20
HC —
co HC M ~ co
H M I~~| NOX LJ
n\_l M r~i
co I LJ
r~i L- J — U NOX
U n P
«C ^ HC h
B u Q Bn
NOX ' — 1 —
U

AI A^ TI AI A^ Ti Ai Ti A^ A2 AI A]^ Tj A^
Test
Combinations Ti T2 Ti AT A2 Ti Ti T,
(2)
T2 T2
Speed-Controlled
Exhaust Gas
lation with
Reclrcu-
Vacuum
Advance Disconnect
'





B


AI

TI

T2





CO
0






CO
^












" ll




NOx
B



AI

T.

T2
-, 100



-
-
-

-

80 g
f4
4J
3
60 -J
tf
o
40 ^
0)
M
0 0
Percent En
-20





    A. = Anaheim Test 1
    T^ = Taylor Test 1

    T. = Taylor Test 2
                         (1)  Data are from Table 4-5.
                         (2)  See Volume III, Appendix H for explanation of
                             Statistical Test Combinations.
Upper 907. Confidence Limit
Mean Emission Reduction

Lower 907. Confidence Limit
     Figure 4-1.  PERCENTAGE EXHAUST EMISSION REDUCTION MEANS AND 90% CONFIDENCE
           LIMITS FOR EXHAUST EMISSION CONTROL RETROFIT SYSTEMS TESTED AT
                   ANAHEIM, CALIFORNIA, AND TAYLOR, MICHIGAN (1)       :
Device  246,  the exhaust gas recirculation and vacuum disconnect system, is clearly  an
NOx control  device.  The CO reduction is also considerable with a pooled mean  level
of 31 percent  for the Anaheim and  Taylor test results.  The  HC reduction pooled mean
was 12  percent.

Device  1, an air bleed to intake manifold type, is clearly a CO control device.   The
HC percentage  reduction is also significantly different than zero to a lesser  degree.
The air bleed  system does not control NOx, as its principle  of operation leans the
overall air-fuel mixture and lean  mixtures generally will increase the NOx emission
levels  because of the availability of additional oxygen.

4.1.1.4 Screening and Developer Exhaust Emission Test Results

Table 4-2 identifies the retrofit  devices that received up to three tests in the
retrofit program, and the devices  for which the developers provided test data.
                                           4-16

-------
The significant comparisons with devices tested on a vehicle basis are highlighted
below for those devices with comparable types and numbers of tests.

Device  10, an exhaust gas recirculation system with vacuum advance disconnect, showed
essentially the same CO and NOx emission reduction effectiveness as its fleet tested
counterpart, Device 246.

In the air-bleed-to-intake-manifold category, Device 42 was directly analogous to
Device  1 as a significant CO reducer, with some HC reduction effectiveness.  Device
401, which also acts as an air bleed to the intake manifold, showed equivalent
emission control characteristics,,  Device 325, an air-bleed-to-intake-manifold
system with crankcase blowby recirculation, showed reductions equivalent to the air
bleed systems evaluated in the test program (HC and CO reductions with essentially
no change in NOx).  Device 33, a carburetor main nozzle modification, showed
significant emission reduction for HC and CO, but NOx increased 43 percent.

Device  69 followed the pattern of Device 175, as an ignition timing modification with
lean idle mixture adjustment, in providing HC, CO, and NOx reduction.

Device 469, a rich thermal reactor combined with exhaust gas recirculation, showed
equivalent emission reductions to the catalyst system (Device 96) tested on the vehicle
fleet, with substantial reductions for all three exhaust pollutants.

Device 52 is representative of the gaseous fuel systems.  The high air-fuel ratios
which these systems enable make reductions of all three exhaust pollutants possible.
It is generally agreed that HC emissions from gaseous fueled vehicles have less
photochemical smog reactivity than those from gasoline fueled vehicles.  No Federal
reactivity scale has been defined to allow for quantitative correction of this
difference between fuels.  In California, a reactivity factor is being used in the
test procedure for gaseous fuel system conversions.(1)

4.1.2    Crankcase Emission Control Systems Group

Crankcase control systems could reduce total vehicle HC emissions up to approximately
20 percent from an uncontrolled vehicle. (2)  This type of retrofit device may indirectly
affect exhaust emissions.  This characteristic could be caused by the flow charac-
teristics of the system.  If the total flow of a blowby control system far exceeds the
blowby flow rate produced by the engine, then it becomes a mixture leaning device,
such as an air-bleed-to-intake-mariifold system.  The device still has an advantage
over the air bleed in that crankcase blowby is being controlled and the crankcase is
being purged with ventilation air»

No retrofit devices were tested in this group, since considerable data already exist
on these devices,  which have been in use on new cars in California since 1961 and
nationally since 1963.   Exhaust emission data were obtained on five devices in this
category (Table 4-3).
(1) "California Exhaust Emission Standards and Test Procedures for Motor Vehicles
    Modified to Use Liquid Petroleum Gas or Natural Gas Fuel," State of California
    Air Resources Board, 28 November 1969.
(2) "Control Techniques for Carbon Monoxide, Nitrogen Oxide,  and Hydrocarbon Emis-
    sions from Mobile Sources," National Air Pollution Control Administration Publi-
    cation No. AP-66, March 1970.
                                        4-17

-------
A potential problem could result from use of the air-bleed retrofit systems in com-
bination with positive crankcase ventilation (PCV) and exhaust gas recirculation
systems; this may cause excessively lean air-fuel carburetion.  This could result
from a combination of high ventilation airflow rates through the PCV valve and/or
the additional air provided by an air-bleed system installed between the PCV valve
and the intake manifold.  High crankcase ventilation airflow rates occur on PCV
equipped vehicles with  low blowby flow rates.  As the vehicle accumulates mileage
blowby  flow rates generally increase and ventilation airflow of the PCV system de-
creases.  The possibility of excessive air ventilation decreases with age.

On the  other hand, if an older used vehicle with a PCV system has a relatively rich
fuel mixture, an air-bleed retrofit system could show some HC and CO emission
reduction, provided that the air-bleed device flow rate is not excessive.  In using
the air-bleed approach  for HC and CO control, criteria would have to be established
to identify "lean" and  "rich" cars and the allowable carburetor air-fuel mixture
changes caused by the air-bleed system.  Additional considerations on retrofit de-
vice vehicle applicability are presented in Section 6.

4.1.3  Fuel Evaporative Emission Control System Group

Carburetor and fuel tank evaporative emission control systems could reduce total
vehicle hydrocarbon emission up to 20 percent from an uncontrolled vehicle.  Without
evaporative loss control, as much as 29 grams of fuel can evaporate during the hot
soak period following shutdown of a hot engine.   This type of system, like the blow-
by controls, may indirectly affect exhaust emissions.(1)

No evaporative control devices were found to be available for retrofit use or under
development other than Device 165, a combination emission .control system which in-
corporates gas tank and crankcase vapor controls.

Use of fuel evaporation emission control systems was initiated in 1970 on new motor
vehicles sold in California and in 1971 on new vehicles sold nationally.  Two fuel
evaporative systems have been designed for production use.  These are based on two
different approaches to fuel vapor recovery.   One system stores the fuel vapor in
the crankcase and the other stores the vapor in a carbon canister during soaking
periods (engine off).   The vapors are purged from the crankcase or canister when
the engine is running.   The effectiveness of either system for reducing overall
vehicle emissions should be equivalent.

4.2  DRIVEABILITY AND SAFETY

The driveability and safety of retrofit devices  were evaluated as related factors
in a device's overall effectiveness, because many driveability problems may also
be safety problems.
(1) Deeter, W.F., H.D. Daigh, and O.W. Wallin, Jr., "An Approach for Controlling
    Vehicle Emissions," SAE Paper 680400, May 1968.
                                       4-18

-------
4.2.1  Exhaust Emissions Control System Group

All of the devices tested belonged to the exhaust control retrofit group.  The
driveability tests were performed in accordance with the test procedures of the
Automobile Manufacturers Association (AMA).  These procedures include both cold
and hot driving modes for determining the number of times required to start the
vehicle, cranking time per start, rough idle, stall at idle, stall at various speed
increments, backfire, detonation, surge, stretchiness, hesitation, and acceleration.
These driveability characteristics were divided into two categories, critical and
general; the former consisted of backfire and stall under both hot and cold driving
modes, and the latter consisted of all other parameters.  Backfire and stall were
considered critical characteristics because of their possible adverse effect on the
driver's safety and the vehicle's functional integrity.  Each characteristic was
measured in terms of either no problem; or trace, moderate, or heavy problems.  Fuel
consumption, measured during the emission tests, was an additional factor analyzed
for impact on driveability and also was an input to the cost calculations.

Driveability characteristics were determined for the test vehicles with and without
the retrofit devices installed.  Additional tests were performed on four devices,
including mountain, desert, and urban driving, to determine the effects of operating
extremes on vehicle driveability with the devices installed.  In the quantitative
calculation of the driveability performance or index of a device, if there was no
change in the driveability parameters with the retrofit device installed, as compared
to the same vehicle without the device, the general Driveability Index was equal to
zero.  This was the best case (unless driveability was improved by the retrofit
device), since the Driveability Index was calculated as a penalty index.  For
example, should an acceleration loss of three seconds be the only consequence of
device installation the index would equal 1.25.  This high of an index exceeds the
acceptable limit level of 1.0 shown in the evaluation criteria of Table 1-2.

Test and analysis of the retrofit devices for their effect on safety was based on
such factors as exhaust gas leakage, leakage of raw fuel, introduction of raw fuel
to a source of ignition, engine failure or loss of power, and introduction of
temperatures excessive  for human or vehicle  safety.

Table 4-6 presents the driveability results for the 11 devices tested.  The general
driveability and safety characteristics of the representative devices that
received up to 18 tests are summarized in this table:

     a.   Air Bleed to Intake Manifold Devices:  These devices have to be carefully
          tuned as part of the engine system, since they affect the air-fuel
          mixture.  Too lean a mixture can cause rough idle, hesitation, surge, and
          slower acceleration.  In the devices evaluated, traces of these problems
          were evident.

          There were no safety problems identified for the air bleed devices.
          Gasoline mileage improved 4 percent, while acceleration times were
          10 percent slower on the average.
                                       4-19

-------
Table 4-6.  DRIVEABILITY AND SAFETY CHARACTERISTICS FOR DEVICES
                        TESTED IN RETROFIT PROGRAM
DEVICE
NO.
1
96
175
246
10
33
42
69
245
288
295
DESCRIPTION

Air Bleed to Intake
Manifold
Catalytic Converter with
Distributor Vacuum
Advance Disconnect
Ignition Timing Modifica-
tion with Lean Idle
Adjustment
Speed-Controlled Exhaust
Gas Reclrculation with
Vacuum Advance Disconnect

Throttle-Controlled Exhaust
Vacuum Advance Disconnect
Carburetor Modification,
Main Jet Differential
Pressure
Air Bleed to Intake
Manifold
Electronic- Controlled
Vacuum Advance Discon-
Lean Idle Modification
Variable Camshaft
Timing
Carburetor Main Discharge
Nozzle Modification

AVERAGE
DRIVEABILITY
INDEX
0.138
0.304
0.118
0.113
0.441
0.181
0.116
0.087
0.895
-0.459
3.261(7)
NO. OF
TESTS
18
17
10
13
2
2
2
3
1
1
1
CRITICAL
DRIVEABILITY
CHARACTERISTICS (1)
Less tendency to stall
during cold start accel.
modes (No. of occurrences
Insignificant)
More stalls during cold

leant)
More stalls during cold
start acceleration modes
Insignificant)
No effect
No effect
No effect
More stalls during cold
start acceleration modes
significant; based on
2 tests only)
More stalls during cold
(No. of occurrences
insignificant)
No effect'
No effect
More stalls during cold
(No. of occurrences
significant; based on
one test only)
GENERAL
DRIVEABILITY
CHARACTERISTICS (1)
More stall at Idle and
acceleration hesita-
tion during cpld modes
• Longer starting
times; more hesita-
tion, and stretch-
start modes
• Idle was Improved
during cold and hot
start modes

modes
More stumble and
hesitation during
cold start modes
'• More stumble, hesi-
tation during cold
start modes
• Increased accelera-
tion times
• More stumble and
cold start modes
• Longer starting
times during hot
start modes
Longer starting times
during hot start
• Worse idle per-
formance during
cold start modes
• Longer starting
times during hot
start modes
• Less detonation
during hot start
modes
More hestiation
modes
More stretchiness
during cold start
modes
Shorter starting
times and less
stumble during
cold start modes
• Longer starting
at idle during
cold arart modes
• More hesitation
during hot start
modes
• Shorter starting
times during hot
start modes

SAFETY
HAZARDS
None
Potential
fire
hazard (4)
None
None ( 5)
None (5)
Possible
fire
hazard (6)
None
None
None
None
None
AVERAGE CHANGE, %
0-60
ACCEL(2)
-10
-5
-6
-6
-19
-5
-3
-2
-38
17
-12
GASOLINE
MILEAGE (3)
4
-1
-10
7
0.5
13
7
0
-10
-6(8)
-10
(1) Comments describe vehicle operation with device installed as compared to standard vehicle without device.
(2) Negative signs indicate acceleration degradation.
(3) Negative signs indicate less miles per gallon during 1972 Test Procedure emission test.
See Appendix L, Volume III for fuel consumption.
(4) Potential fire hazard due to excessively high converter temperatures.
(5) Assumes good maintenance is practiced to prevent recirculated exhaust leakage.
(6) Potential fire hazard due to raw fuel syphoning to intake manifold.
(7) It is possible that this DI Is invalid due to an inadvertent maladjustment of the ignition timing.
(8) Based on two measurements performed during emission tests using the 1972 Federal Test Procedure. Only one drlveablllty test was valid.
                              4-20

-------
     b.    Exhaust Gas Reactor Devices:  The catalyst device evaluated in the retrofit
           program required no-lead fuel.  Detonation was evident in some of the test
           vehicles.  Acceleration times were about 5 percent slower with the
           device installed.  Gasoline mileage decreased 1 percent on the average.

           For  safety considerations these devices have to be insulated or located
           such that their inherently high operating temperatures cannot injure
           operating or maintenance personnel, or cause thermal damage to vehicle
           structure and components.

     c.    Ignition Timing Modification:  Electronic or mechanical control of
           ignition timing to retard the spark caused slower acceleration times of
           6 percent.  Gasoline mileage with these devices decreased by as much
           as 10 percent (Device 175).

           These devices are characteristically only operative at idle and low- to
           mid-rpm ranges, where emissions are greatest and, therefore, do not affect
           normal cruising driveability.  Some stumble and hesitation was observed
           during the cold start modes of operation.

           There appear to be no safety problems, provided that all components are
           maintained satisfactorily.

     d.    Devices Incorporating Exhaust Gas Recirculation with Distributor Vacuum
           Advance Disconnect:  Recirculated exhaust gas affects driveability
           slightly, because of the dilution it causes in the air-fuel mixture.
           When combined with retarded spark, as in the case of Device 246, this
           dilution caused acceleration times to be 6 percent slower.  Gas mileage
           was  improved by 7 percent on the average for Device 246.

           No safety problems were evident in the devices examined; however, good
           maintenance would have to be practiced to ensure that the recirculated
           exhaust gas does not leak into the engine or passenger compartments and
           thereby introduce a safety problem.

4.2.2  Crankcase Emission Control System Group

These devices  have acceptable driveability and safety characteristics, if installed
and maintained satisfactorily.  Since the devices evaluated are basically the same
as the ones already in use on vehicles, driveability and safety tests were not
conducted.

4.2.3  Fuel Evaporation Emission Control System Group

Although a device of this type was not found to be available for retrofit application,
such devices should not present any driveability or safety problems.  However, if
not properly designed, fire or explosion hazards may occur.
                                        4-21

-------
4.3  RELIABILITY AND MAINTAINABILITY

Reliability and maintainability analyses were conducted on those devices for which
sufficient system data were obtained or developed.  These analyses were mainly
limited by the completeness of functional and design information obtained from the
developers.  The evaluation indicated that reliability and maintainability of most
of the devices could be improved by careful detailed design and production engineer-
ing, since the devices in general have not been designed to meet specific reliability,
maintenance, or producibility objectives.

The results of the reliability analysis indicated that none of the retrofit devices
evaluated would have a mean-miles-before-total-failure (MMBTF) of less than
50,000 miles if normal automotive design and fabrication standards are followed
in their production design and manufacture.

4.3.1  Reliability and Maintainability Analysis Approach and Results

The approach used in the reliability and maintainability analyses was to compare
device components with similar or identical conventional automotive components,
and to estimate reliability and maintenance requirements based on the generally
accepted characteristics of the comparable automotive components.  It was assumed
that the ultimate design of the device would reflect the same level of reliability
and requirements for maintenance found in the similar automotive components.  Thus,
the reliability estimates and maintenance requirements determined for a given
component (e.g., solenoid-actuated exhaust gas valve, vacuum hose, thermostatic
switch) were relatively uniform for all devices incorporating similar components.

The criteria used in determining acceptable reliability and maintainability
characteristics were those established by the California Health and Safety Code
for retrofit device accreditation (refer to Table 1-2).  These are as follows:

     a.   The reliability of a device shall provide an expected useful life of
          at least 50,000 miles of operation.

     b.   Maintenance shall not be required more than once each 12,000 miles
          and shall not cost more than $15 for labor and material each time.

4.3.1.1  Reliability and Corrective Maintenance Analysis Procedure

Corrective, or repair, maintenance requirements were analyzed along with reliability,
to establish replacement parts costs and labor costs for repair.  Corrective
maintenance is defined as all maintenance and inspection action resulting from
failure of a device totally or partially as a result of component failure.  This
type of maintenance is the opposite of preventive, or planned maintenance performed
to keep a device in good working order.

To estimate reliability and corrective maintenance costs, a listing was made of all
the components comprising each retrofit device, and the components were evaluated
individually for reliability and maintainability characteristics on the basis of
comparable counterparts in a conventional automotive system.  For example, a  sole-
noid actuator was considered similar to a starter solenoid, and a vacuum regulated
                                        4-22

-------
actuator was considered similar to a vacuum advance unit.  Using this comparative
basis for evaluation, the following values were estimated for each component of the
retrofit device:

     a.   Failure Interval;  This was estimated in terms of the parameters, mean-
          miles-before-partial-failure (MMBPF) and mean-miles-before-total-failure
          (MMBTF).  The MMBPF was the expected number of miles a device would be in
          operating condition (available to perform its function), based on the
          mean of all partial failures it might have during its service life, while
          the MMBTF was the total service life of a device based on all complete
          failures after which a device would have to be replaced as a unit.

     b.   Replacement Parts Cost;  This cost was estimated on the basis of the cost
          of a comparable automotive part, considering the retail cost of device
          components given by the developer.

     c.   Labor for Corrective Maintenance;  This was the labor associated with
          fixing each component failure and was based on the average California
          repair rate of $12.50 per hour.

Each retrofit device was individually evaluated for component failures.  The failure
intervals, replacement parts costs, and corrective maintenance actions estimated for
the retrofit devices with sufficient data are tabulated in Table 4-7.  In this table,
the individual devices are listed according to general group classifications, and
the corrective maintenance actions associated with a component failure are reduced
to a list of 18 typical repair actions.  Component material costs and labor hours
associated with the repair actions for each device are listed in the appropriate
matrix box.   The MMBPF was estimated as the mean of the component replacement
intervals.  In most cases, replacement interval data were not available to
distinguish total from partial failures;  hence the MMBPF is the same as the MMBTF.

4.3.1.2  Reliability Analysis Results

The following observations are based on the reliability estimates shown in Table 4-7:

     a.   Almost any of the retrofit device components, if designed to normal
          automotive functional, cost, and production standards, may be expected to
          have a life of 50,000 miles or more, with reasonable preventive
          maintenance practices.

     b.   Systems which use valves, switches, and electrical sensors or contacts
          are prone to failure in proportion to the number of these components used.
          Generally, exhaust and induction control systems which incorporate
          electromechanical functions requiring valves, switches, and sensors,
          are more susceptible to reliability problems and consequently have greater
          need for preventive maintenance.  MMBTF's estimated for these devices
          were usually 50,000 miles.  Conversely, induction system modifications
          having no moving parts, such as carburetor jets and intake manifold
          inserts have high reliability (MMBTF equal to or greater than 75,000 miles),
          but generally involve some periodic inspection to verify that ignition
          and carburetion tuneup adjustments are maintained and that deposit buildup
          has not occurred.
                                        4-23

-------
Table 4-7.  RELIABILITY AND CORRECTIVE MAINTENANCE  ESTIMATES  OF DEVICES
                           EVALUATED IN RETROFIT PROGRAM
o
33
U
a
a
DEVICE DESCRIPTION
REPLACEMENT PARTS COST ($) /REPAIR LABOR HOURS
os
IGNITION DEVICE/
HEATING ELEMENT/
HEAT EXCHANGER
CATALYST
SPRINGS /CABLES
POINTS/CONTACTS/
SENSOR
P-
fi
VALVE
TUBING/NOZZLES
« S
ES U
fi
ELECTRONIC ASSEMBLY
1
IGNITION COIL
,
BACK PRESSURE/FLOW
CONTROL VALVE
i

i
H
b.
U
FAILURE
INTERVAL
iJ
\ll
E 0. C-
g S
as*
l||
PARTS
COST
(5)
AVERAGE COST <
REPAIR PARTS
LABOR
HOURS
1
li
GROUP 1 EXHAUST EMISSION CONTROL SYSTEMS
Type 1.1 Exhaust Gas Control Systems
1.1.1 Catalytic Converter
62
93
96
292
Catalytic Converter
Catalytic Converter with Exhaust Gas
Reclrculation, Spark Modification,
Catalytic Converter with Distributor
Vacuum Advance Disconnect
Catalytic Converter
Insufficient Data
Insufficient Data





15.00
0.50






L5.00
1.05







5.00 >
^I.IO



12.00,








45.00
0.75


SO.OOx
1.60



















3.00,







125.01
4.00
60.00^


50
50


50
50


35.00
40.00


1.67
0.75
. 1.1.2 Thermal Reactor
31
244
463
468
Thermal Reaction by Turbine Blower Air
Injection
Rich Thermal Reactor
Rich Thermal Reactor with Exhauet Gas
Reclreulation and Spark Retard
Lean Thermal Reactor with Exhaust Gas
Reeireulatlon


Insuf
Insuf


iclen
Iclen


: Data
Data




















20.00,







50.00.
•"1.60



























80.00
''Ton
&75.0C


50
75


50
75


SO.Offl 3.00
275.0(


8.00


1.1.3 Exhauat Gas Afterburner
308
425
Exhaust Gaa Afterburner
Exhaust Gas Afterburner


2.50,
^0.25
10.00,
-"oTso


2











25.00
-'oTso
50.00
•'o.so

45.00.




6.25
^25







55.00,
"U25
140.00
^1.50
50
50
50
50
18.00
61.25
0.50
0.75
1.1.4 Exhauat Gas Filter
164
Exhauat Gas Filter
I 1
Insufficient Data



















1.1.5 Exhaust Gas Backpressure
322

P
Insufficient Data



















Type 1.2 Induction Control Systems
1,2.1 Air Bleed to Intake Manifold
1
42
57


401
418
433
458 ,
462


Air Bleed to Intake Manifold
Air Bleed with Exhaust Gas Recirculation
and Vacuum Advance Disconnect


Air-Vapor to Intake Manifold
Air Bleed to Intake Manifold
Air-Vapor Bleed to Intake Manifold
Air Bleed to Intake Manifold
Air Bleed to Intake Exhaust
Manifolds


1.50,


Insuf

Insuf





icien

icien





Data

Data
Insufficient Data
2. 00,




























4.00,
"1^25






12.50,

z
3.00,
-^30
2.50

3.00
"oTso














15.00,
15.00.
^6\75

15.00,
^0.60




















2.00^

1.00,
"6\25
2.00,
^.25
2.50,
•^oTso

2.00,
1h25











8.00


7.50,
^60


7.5(i,
^60




















48.00
X1.25
10.00
41.00
40.00
33.00.

40.00,


75
75
50
50
50

50


75
75
50
50
50

.50


14.50
10.00
10.00
13.50
13.25

13.50


0.75
1.00
1.00
0.60
0.60

0.60


                                  A-24

-------
Table 4-7.  RELIABILITY AND CORRECTIVE MAINTENANCE ESTIMATES OF DEVICES
                           EVALUATED IN RETROFIT PROGRAM (CONT)
u
a
DEVICE DESCRIPTION
REPLACEMENT PARTS COST {$) /REPAIR LABOR HOURS
CARBURETOR COMPONENT
IGNITION DEVICE/
HEATING ELEMENT/
HEAT EXCHANGER
CATALYST
SPRINGS/CABLES
ll
On V)
fc
,
1
TUBING/NOZZLES
HOUSING/CHAMBER/
CONTAINER
1
6-
3
|
i
1
IGNITION COIL
,
BACK PRESSURE/
FLOW CONTROL VALVE
1
£
RETROFIT DEVICE
FAILURE
INTERVAL
PARTIAL FAILURE
CMMBPF) (1,000 MILES)
MEAN MILES BEFORE
TOTAL FAILURE
(MMETF) (1,000 MILES)
PARTS
COST
AVERAGE COST OF ~
REPAIR PARTS (CRp). ~
LABOR
HOURS
i
1.2.2 Exhaust Gas Recirculation
10
245
246
Throttle-Controlled Exhaust Gas Recir-
culation with Vacuum Advance Disconnect
Variable Camshaft Timing
Speed-Controlled Exhaust Gas Reeircu-

3.50,
"0.60


,50,
"0.60

10.00,
'(h50






2.50,





2.00,
'0.30

15.00
'6/75
8.0J,

15.00.
'6\75
1.50,
'0.15

3.00,











2.00,
"6^25





6.00.
"oTso






55.00,
50.00,
'^25
61.00,
'2^25
50
75
75
50
75
75
11.00
50.00
16.00
0.55
2.25
0.87
1.2.3 Intake Manifold Modification
172
384
430
440
Intake Manifold Modification
Air-Fuel Mixture Diffuser
Induction Modification
Air-Fuel Mixture Deflection Plate

Insuf



iclen



Data


























































60.00

10.00
3.00
75
75
75
75
75
75
75
75
60.00

10.00
3.00
1.50

0.75
0.75
1.2.4 Carburetor Modification
33
56
268
294
295
317
Carburetor Modification, Main Jet
Differential Pressure
Crankcase Blowby and Idle Air Bleed
Modification
Modification
Exhaust Gas Recirculation with
Carburetor Modification


Carburetor Modification with Vacuum
Advance Disconnect

5.50,
0.75

Insuf



9.00,
'0\70

Icien





Data





















21



































A. 00,
'6^15




























8.65
35.00
''T.25

70.00
'oT75
13.95
75
75
75

75
75
75
75
75

75
75
8.65
12.50
25.00

70.00
13.95
1.00
0.72
1.25

0.75
0.75
1.2.5 Turbocharger
100
1 1
Turbocharger Insufficient Data



















1.2.6 Fuel Injection




175


Type 1.3 Ignition Control Systems
.3. g g
connect and Carburetor Lean Idle
Modification
Ignition Timing Modification with Lean
Idle Adjustment
1
Insufficient Data























15.00
'l.OO












25.00,
'6^35




2.00,
0.25















50.00
'UOO
32.00
'l.OO


75
75


75
75


23.00
32.00


0.65
1.00
1.3.2 Ignition Spark Modification
23
95
259
268
296
Electronic Ignition Unit
Ignition Spark Modification



P g 8
Ignition Timing and Spark Modification
Insuf
Eicien
Data
Insufficient Data

















































































50.00
"O.T5
60.00
20.00


75
150
75


75
150
75


50.00
60.00
20.00


0.75
0.75
0.25
                                   4-25

-------
Table 4-7.  RELIABILITY AND CORRECTIVE MAINTENANCE ESTIMATES OF DEVICES
                           EVALUATED IN RETROFIT PROGRAM (CONCL)
DEVICE NO.

DEVICE DESCRIPTION


REPLACEMENT PARTS COST ($)/REPAIR LABOR HOURS
CARBURETOR COMPONENT
IGNITION DEVICE/
HEATING ELEMENT/
HEAT EXCHANGER
CATALYST
Oi
II
ou
cu tn
SPARK PLUGS
SWITCH
I
TUBING/NOZZLES
HOUSING/CHAMBER/
CONTAINER
a.
ELECTRONIC ASSEMBLY
u
1
IGNITION COIL
ADAPTER
BACK PRESSURE/
FLOW CONTROL VALVE
!
RETROFIT DEVICE
FAILURE
INTERVAL
,ES BEFORE
FAILURE
(1,000 MILES)
MEAN MI
PARTIAL
(MMBPF)
1
1J
» OS C
ill
PARTS
COST
11
AVERAGE
REPAIR
LABOR
HOURS
ct
M
<
C£
H *--
E ~

1.4.1 Alternative Gas Conversion
52
459
460
461
464
466
LPG Conversion




It
Compressed Natural Gas Dual-Fuel
Conversion
LPG Conversion with Exhaust R
Recirculation
Converter
eactor
st Gas


LPG-Gasoline Dual-Fuel Conversion


Insuff
Insuf




iclent Data
icien
Insufficien

Data
Data



(2)


(2)







































































457.95
112.00
300
451.14
^-^\ 100
I 12.00



575.00
1^\ "
"Is. oo


457^5
300
300
300
75

300
.57.9!
157.9!
(2)
575. OC

(2,
12
12
(2)
18

(2)
1.4.2 Fuel Additive
182
282
457
465
Fuel and Oil Additive
LP Gas Injection
Water Injection
Fuel Additive
I
Not A

ppllca

Insufficient
Die

Data
Not Applicable













5.00.
IhSO



20.00,
-lj.75



5.50,
1^50















12.00
1.25



















80.00,
'^OO



50



50



24.50



1.20


1.4.3 Fuel Conditioner
36
279
Fuel Conditioning by Exposure
Electromagnetic Field
to

Fuel Conditioner
Type 2.1 Closed Systems
24
170
315

1
Insufficien


Data






























10.00
'oTso

50

50

10.00

0.50
GROUP 2 CRANKCASE EMISSION CONTROL SYSTEMS
Heavy Duty Positive Crankcase Control
Valve with Air Bleed




Closed Blowby Control System























3.00
0.50














2.0oJ
0.25












24.40
1>T75
17.00
''1/75
50.00
100
100
50
100
100
50
24.40
17.00
18.33
0.75
1.75
0.75
Type 2.2 Open Systems
160
427
Closed or Open Blowby Control
with Filter
Closed or Open Blowby Control
with Filter
System
Syste
m














2.50
0.75
3.00
'oiTs








1.00
0.25
1.00,
0.25


3.00
0.75
4.00
0.75




53.50J
^-'"1 75
1.25
52.00J
^\ 50
i.zsl
75
50
15.00
15.00
0.75
0.75
GROUP 3 EVAPORATIVE EMISSION CONTROL SYSTEMS
467
Fuel Evaporative Control System
Insufficient Data



















GROUP 4 EMISSION CONTROL COMBINATIONS
59
165
408
469
Three-Stage Exhaust Gas Contr
ol Sys
Exhaust Gas Afterburner/Recirculati
with Blowby and Fuel Evaporation
with Intake Vacuum Control an
Turbulent Mixing
Rich Thermal Reactor with Exh
Recirculation and Particulate
LEGEND:
515.00 	 —
Replacement parts cost
d
tern
on

aust Gas
Control

15.00,

Insuf

9.00
0.75
Insuf
Icien
10.00

icien
t Data


Data









2.00
-0,21






15.00
:2^Z5.
12.00
"liT^


5.00
0.40















3.00
5.00
0.50


8.00
0.45



4.00
Q.70



3.00
(3)^-'
'"0.15



3.00
-2.-25_


175.00
'5.00
20.00


50
50


50
50


19.50
11.50


0.75
0.81

NOTES: (1) Mean time for one repair action
-— 	 0.50 Hr Labor to Replace (2) Cost and labor to replace Bowden cable depends on specific installation
details. C and MTTR depend on these estimates.
(3) Three control valves
                                  4-26

-------
     c.   Most retrofit emission control systems  (except ignition control systems),
          tend to  include multiple components which represent possible failure
          points.  However, these components can  usually be repaired without
          replacing  the entire system.

     d.   Ignition control systems are usually transistorized devices.  If designed
          properly,  their MMBTF is greater than 75,000 miles, but failure occurs
          suddenly.  These devices generally have to be replaced as a total unit
          upon failure as a whole or in part.

     e.   Those induction modifications that have no moving parts may generally
          be more  reliable.  Air-bleed and exhaust gas recirculation induction
          modifications are generally more failure prone, because they contain
          more moving parts.

In summary, all retrofit devices evaluated are considered to have acceptable
reliability characteristics if conventional automotive design standards are applied
to the production  models and if good preventive maintenance practices are followed
during their service life.

4.3.1.3  Maintainability Analysis Procedure

The method for estimating retrofit maintainability requirements was similar to the
method used for reliability.  Maintainability was analyzed in terms of the pre-
ventive maintenance  required to keep a device in  satisfactory operating condition
on a planned, scheduled basis.

Each retrofit device was examined for probable preventive maintenance requirements
by considering it  comparable to a conventional automotive counterpart.  Using this
approach, it was reasonable to conclude that an air filter should be changed
every 12,000 miles, or a valve assembly cleaned and reset every 25,000 miles.  For
each retrofit device examined the following information was determined by the
engineering evaluation team:

     a.   Preventive maintenance action - description.

     b.   Maintenance interval - quantified by the mean-miles-before-maintenance
          (MMBM) interval.

     c.   Labor associated with the preventive maintenance action - listed as
          mean-time-to-maintain (MTTM), in hours.

     d.   Material and parts cost for the maintenance action (C^p), in dollars.

Table 4-8 lists retrofit devices by group classification and the preventive main-
tenance actions, associated intervals, and costs.  In this table, the preventive
maintenance actions were condensed to 18 typical actions encompassing the main-
tenance required for all individual devices.  Maintenance intervals (MMBM),
associated labor time (MTTM), and maintenance parts cost were entered for the
preventive maintenance actions applicable to each device.  If the preventive
maintenance of a device required an engine tuneup parameter adjustment, then the
time for this adjustment was included in the device maintenance time.  The labor
and parts costs for complete engine tuneup are excluded from the estimates because
the retrofit contract requirements specifically excluded tuneup as a retrofit method.
                                        4-27

-------
Table 4-8.  PREVENTIVE MAINTENANCE ESTIMATES OF DEVICES
                   EVALUATED IN RETROFIT PROGRAM
DEVICE
NO.
DESCRIPTION
Type 1.1 Exhaust Gaa Control Systems:

62
93
96
292

Catalytic Converter
Catalytic Converter with Exhaust Gas
Recirculation, Spark Modification, and
Lean Idle Mixture
Vacuum Advance Disconnect

Y
REPLACE CATALYST
ll
OIL/FUEL/
INJECTANT
s
g
CLEAN AND REPLACE
UNIT /COMPONENT
CLEAN PARTS/
ORIFICES/VALVES
FUEL FILTERS
I
j
CHECK SWITCH OPERA-
TION (WITH METER)
VALVE ACTUATION
VOLTAGE
CHECK & ADJUST
IGNITION TIMING/
DWELL
CARBURETION
VALVE SETTING
%
1
INSPECT (VISUAL)
PLUGS & POINTS
1
i
Ck,
MEAN-MILES-BEFORE-
MAINTENANCE (MMBM)
(1,000 MILES)
COST MAINTENANCE
PARTS (Cup) $
MEAN-TIME-TO- 1
MAINTAIN (MTTM),HRS
GROUP 1 EXHAUST EMISSION CONTROL SYSTEMS;
Insi
Insi
/30

ffici
fflci
12 /
/•I*
12 :/
:nt Dal
:nt Da


a
a




























































8.33
12


(1)
16.25
2.50


0.27
0.25
1.1.2 Thermal Reactor
31
244
463
468

308
425

Air Injection
Rich Thermal Reactor
Rich Thermal Reactor with Exhaust Gas
Recirculatlon and Spark Retard
Lean Thermal Reactor with Exhaust Gas
Recirculation


Exhaust Gas Afterburner
Exhaust Gas Afterburner



Insu
12 /
/.25
12 /
12 /
ficie



nt Dat




























































12
12
12

3.00
1.25
1.25

.25
0.25
0.25
























12 :/




12 /


12 /
1! './


12 /
/15
X""
12
12
3.00
1.50
0.80
0.45
1.1.4 Exhaust Gas Filter
164
Exhaust Gas Filter
Insufficl nt Data

















1.1.5 Exhaust Gas Backpressure
322
Exhaust Gas Backpressure Valve
Insi
ffici
nt Data

















Type 1.2 Induction Control Systems:
1.2.1 Air Bleed to Intake Manifold
1
42
57
325
401
418
433
458
462
Air Bleed to Intake Manifold
Air Bleed to Intake Manifold
Air Bleed with Exhaust Gas Recirculation
and Vacuum Advance Disconnect
Air-Vapor Bleed to Intake Manifold

P
Air Bleed to Intake Manifold
Air-Vapor Bleed to Intake Manifold
Air Bleed to Intake Manifold
Air Bleed to Intake and Exhaust
Manifolds





In.

Insi
Insi
12 /

12 /
/.10
X

ffici
X
fflci
fflci



%
2.5/
nt Dai
%
nt Dat
'.nt Dat





a

a
8












%
2.5 /



X

X






X











%






12 /
/TlO
12 /
12 /
/.15





































X






















12 /
12 /
















12
12
12
2.5
2,5

2.5


2.50
0
2.50
2.30
12. 50'

2.30


0.30
0.20
0.40
0.50
0.50

0.50


                           4-28

-------
Table 4-8.  PREVENTIVE MAINTENANCE ESTIMATES OF DEVICES
                   EVALUATED IN RETROFIT PROGRAM (CONT)
DEVICE
NO.

10
245
246
DESCRIPTION




Variable Camshaft Timing
Speed-Controlled Exhaust Gas Recircu-

REPLACE CATALYST
AIR, EGR, BLOWBY
FILTER
OIL/FUEL/
I NJECT ANT

CLEAN & REPLACE
UNIT/COMPONENT
CLEAN PARTS/
ORIFICES/VALVES
05
H
,-J
LINES
CHECK SWITCH OPERA-
TION (WITH METER)
Z
VOLTAGE
CHECK & ADJUST
IGNITION TIMING/
DWELL
CARBURETION
VALVE SETTING
SWITCH SETTING
INSPECT (VISUAL)
PLUGS t, POINTS
LINES & HOSES
PIPES & CHAMBERS
MEAN-MILES-BEFORE-
MAINTENANCE (MMBM)
(1,000 MILES)
JCOST MAINTENANCE
| PARTS (Cup) $
MEAN-TIME-TO-
[MAINTAIN (MTTM),HRS
















n/
X-15

6 /
/.W



12 /
/ .05

6 /
/10


12 /
/ .15

b /
/.10




%0

12 X

6 /





^









12
25
6
1.25
0
1.25
0.50
0.50
0.50
1 2 3 Intake Manifold Modification
172
384
430
440

33


288
294


317
Intake Manifold Modification




Air-Fuel Mixture Deflection Plate

1.2.4 Carburetor Modification

Differential Pressure


Carburetor Main Discharge Nozzle
Modification
Exhaust Gas Recirculation with
Carburetor Modification

u r a e en r
Carburetor Modification with Vacuum

Not



Requi



red




X




/.OS
25/
/.08





















































25
25
25
0
0
0
0
0
0.08
0.08
0.08

Not

Not
Ins


Requl

Requ
iffic


red

red
ent Da





.









12/
XlO


Yi/
/.IS
12/
X.10













/ .05























12 /


X/25
12/
XlO



















y
, .05











12


12
12
0
2.00
0

0
0
0
0.30
0

0.50
0.20
1.2.5 Turbocharger
100
Turbocharger
Ins
jffici
ent Da
a

















1.2.6 Fuel Injection



c vie nject on
Ins
.ffici
ent Da
a












X




Type 1.3 Ignition Control Systems:

69
175

Disconnect and Carburetor Lean Idle
Modification

Idle Adjustment



y
/.05















12 /
/ .05



12 /



%

12 /
/.05




X


12

0

0.30

1.3.2 Ignition Spark Modification
23


259
268
296

8



g y


Ignition Timing and Spark Modification
Ins



Not
Not
iffici



Requ
Requ
snt Da



red
Lred
•
a









^






























7
X-25



















%'
j














25




0
0
0


0.50
0
0
                           4-29

-------
Table 4-8.  PREVENTIVE MAINTENANCE ESTIMATES OF DEVICES
                   EVALUATED IN RETROFIT PROGRAM (CONCL)
DEVICE
NO.
DESCRIPTION
Type 1.4
1.4.1
52
459
460
461
464
466
REPLACE CATALYST
K
firi
OIL/FUEL/
INJECT ANT
H
i
CLEAN & REPLACE
UN IT /COMPONENT
CLEAN PARTS/
ORIFICES/VALVES
.J
LINES
CHECK SWITCH OPERA-
TION (WITH METER)
VALVE ACTUATION
VOLTAGE
CHECK & ADJUST
IGNITION TIMING/
DWELL
CARBURETION
VALVE SETTING
SWITCH SETTING
INSPECT (VISUAL)
PLUGS & POINTS
1
1
PIPES & CHAMBERS
MEAN -MILES -BEFORE -
MAINTENAKCE (MMBM)
(1,000 MILES)
COST MAINTENANCE
PARTS (CHJ.) 5
MEAN-TIME-TO-
MAINTAIN (MTTM).,HRS
Fuel Modification;



LPG Conversion
LPG Conversion
Compressed Nat
with Deceleration Unit
jral Gas Dual-fuel Conv.
LPG Conversion with Exhaust Reactor
Pulse Air Injection and Exhaust Gas
Re circulation
Methanol Fuel Conversion with Catalytic
Converter
LPG-Gasoline Dual-Fuel Conversion
1.4.
182
282


465
Fuel



Ir

In



suffi

suffic



ient D

ient D



ata

ta













25 /^
/.25
25 /
/ .25

25 /
/ .25

7
/.25


































































25
25
300
25

25
2.00
2.00

2.00

2.00
0.25
0.25

0.25

0.25
2 Fuel Additive
and Oil Additive
LP Gas Injection


Fuel
1.4.
36
279
Fuel
Elec

j
Additive





Re

In
Re
place

suffic
place
Additi

ient D
e - E

ta
Additive
'ery T



ank Fu
12 :/
/.50


11








12 /
Xio



12 ,/
/fit)



































12


0
0

0

0.70


3 Fuel Conditioner
Conditioning by Exposure to
tromagnetic Field
Fuel Conditioner
Type 2.1
24
170
315
Closed System:
Heavy Duty Positive
Valv

Closed Blowby
Closed Blowby
Type 2.2
160
427
Clos
with

Insufficient D
Not Required
ata
































0

0
GROUP 2 CRANKCASE EMISSION CONTROL SYSTEMS'
Crankcase Control
Control System
Control System













y
/.15
25 /
X30
25 /
X-25

25/
/UO



















7
/.w
25 /
/^25


25 /
Xio












..25
12
25
0
0
0
0.25
0.25
0.75
Open System:
ed or Open
Filter
Blowby Control System
Closed or Open Blowby Control System
with Filter


12 \/
//2S
15^>
/^25



10 /
/<25

^


























12
5
3.00
(2)
3.00
0.25
0.46
GROUP 3 EVAPORATIVE EMISSION CONTROL SYSTEMS
467
Fuel Evaporation Control System






12 /
/^25











12
1.00
.25
GROUP 4 EMISSION CONTROL COMBINATIONS'
59
165
408
469
Three-Stage Exhaust
Gas Control System
Exhaust Gas Afterburner/Recirculation
Exhaust Ga's a
Turbulent Mix
Rich Thermal
Recirculation
nd fllowby Recirculation
ing

Reactor with Exhaust Gas
and Particulate Control
LEGEND:

X
PossiDie
Maintenance

Inter
Thous
Miles
val in— »~
ands of
nainte
Code
12 y
/.5

!,


I.
BUffit
12 /
X-15

suffic
ient D


ient D
ita


ata





12 /
/TlO
12 /
/•25


12 /
/Tio



X








12 /*
X-25






















12 /
/.W



12/^
/ .05







12
12


2.50
2.00


0.50
0.50

NOTES: (1) $16.25 is the cost of replacement catalyst for an 8-cylinder
lance action required. engine every 25,000 miles; the average C^, for use in the
evaluation methodology is $5.42.
(2) $3.00 la the estimated cost of filter replacement every 15,000
Preventive miles; the average C-m for use in the evaluation methodology Is
/Maintenance $1.00.
Labor-Hours
                           4-30

-------
4.3.1.4  Maintainability Analysis Results

The following observations were made for the comparative maintenance estimates shown
in Table 4-8:

     a.   Most of the retrofit devices examined in this program have preventive
          maintenance intervals (MMBM) equal to or greater than 12,000 miles.   The
          exceptions are the alcohol-water injection systems (Devices 325,  401, and
          433) which require refill and metering valve adjustment or cleaning  about
          every 2,500 miles.  Also, Device 246 requires cleaning of the EGR valve
          every 6,000 miles.

     b.   Approximately 75 percent of the devices require 0.5 hour or less  to  main-
          tain.  The associated costs for maintenance parts are less than $3.00 for
          most of these devices.

          The catalyst system (Device 96) requires a new change of catalyst at
          25,000-mile intervals at a cost of $20 for an 8-cylinder engine and
          $15 for a 6-cylinder engine.

     c.   Maintenance requirements generally increase with the number of filters,
          valves, electrical switches and hoses incorporated in the retrofit system.

     d.   Solid-state ignition modification systems reportedly require no preventive
          maintenance.

In summary, most of the retrofit devices examined appear to have reasonable periodic
maintenance requirements and maintenance intervals of no less than 12,000 miles.

4.3.2  Effect of Retrofit Device Installation on Vehicle Reliability and
       Maintainability

The possibility of increased maintenance and decreased reliability in a motor  vehicle
as a result of a retrofit device use can be as unacceptable as the reliability and
maintenance characteristics of the device itself.  Accordingly, each device was
examined for its impact on the reliability and maintenance of the vehicle on which
it might be installed.  The observations presented below are of a general nature
based on past experience with emission control systems.  The durability tests  that
will be reported in Volume VI should provide some actual data to substantiate  these
observations.  The following observations were made:

     a.   The devices using ignition spark retard as an approach for emission con-
          trol may cause engine overheating.  A majority of these types of devices
          have coolant temperature sensors which restore spark advance if overheat-
          ing occurs.  The possibility of exhaust valve damage and the adverse
          effects of  long-term exposure of other related engine components to in-
          creased engine heat must be considered with  these devices.
     b.   Exhaust gas recirculation devices may pose two problems:   (1) recirculation
          may provide a troublesome source of induction system contamination,  and
           (2) the carburetion system may require more  frequent tuning  to provide
          satisfactory driveability.

     c.   Recirculation of crankcase gases to the carburetor base and air inlet
          (closed systems) contaminates the carburetor and may contribute to in-
          creased carburetor maintenance requirements.

     d.   Use of catalytic reactors, thermal reactors, and exhaust gas reactor mani-
          folds has potential problems of increased exhaust backpressure and higher
          temperature; this may result in hotter valve operation.


                                       4-31

-------
      e.    Capacitive  discharge  ignition  systems may require more.frequent replacement
           of  the  high voltage wires and  coil used in conventional ignition systems,
           because of  increased  susceptibility  of conventional system components to
           deterioration.

 4.3.3 Retrofit Emission  Inspection Requirements

 An inspection program is  recommended as  a necessary part of any program of vehicle
 emission  control  incorporating  retrofit  devices.  Each of the 65 retrofit systems
 evaluated have specific inspection and maintenance requirements which control their
 installation  and  use.  Although these requirements may vary from one device to the
 next,  they all have in common the objective of reducing vehicle emissions.

 Vehicles  equipped with an exhaust control device should receive an emission test to
 verify satisfactory device operation in  terms  of actual emission reduction.  This
 test  is required  because  of  the many variables that used cars and installation
 personnel can introduce to make a retrofit device ineffective.
 The retrofit  crankcase blowby control device should be inspected for correct func-
 tional operation  to the device  manufacturer's  specifications.  There is no information
 on inspection requirements for  retrofit  fuel evaporative control systems.

 4.3.3.1   Retrofit Program Inspection and Maintenance Requirements

 To  achieve maximum effectiveness of the retrofit device installation, each used
 vehicle within the jurisdiction of a retrofit program should be inspected and
 adjusted  for minimum emissions  at the time of retrofit device initial installation.
 Also periodic  inspections of the device operation and engine tuneup should be
 conducted.  A  Northrop Corporation study concluded that vehicles experience degrada-
 tion  in exhaust pollutants as they accumulate mileage and age.(l)  Lower levels of
 emissions  are  achievable when vehicles are serviced and adjustments made to engine,
 carburetor, and ignition  systems.

 Most of the retrofit devices evaluated were found to require maintenance usually at a
 frequency  of  12,000 miles.  Depending on the driving habits of individual motorists,
 this would require servicing the device periodically at an interval of once every
 12-24 months.  The recommended  interval and maintenance procedure would be dependent
 on  the respective device and manufacturer.  Requirements for defective or worn parts
 replacement, along with the procedures,  must be defined by the retrofit manufacturer
 based on  reliability and maintainability analyses conducted prior to State and/or
 Federal certification.

 4.3.3.2  Emission Inspection Criteria

 Inspection criteria should be established to identify those retrofit devices and
 systems that have failed or are marginal in performance,  and thus require repair.
Prior to instituting an inspection program,  sufficient empirical data on the certi-
 fied devices and systems should be gathered to define and relate failures and
performance levels to specific corrective actions.   The minimum emission and inspec-
 tion criteria must include the  following:
(1) Northrop Corporation Electro-Mechanical Division in association with Olson Labora-
    tories, Inc., "Mandatory Vehicle Emission Inspection and Maintenance," Part B,
    Test Program Final Report, Contract ARE 1522 (California Air Resources Board),
    Northrop Report No. 71Y240A (two parts), 10 December 1971.
                                        4-32

-------
     a.   Exhaust Control Device Emission Criteria;  Exhaust emission inspection of
          retrofit devices would require measuring HC, CO, and NOx levels.   Emission
          limits for inspection would be established for the controlled pollutants.
          In selecting a retrofit device inspection procedure, careful consideration
          should be given to the compatibility of the procedure for application to
          new model vehicles for continued use after uncontrolled vehicles  phase out.

          For those retrofit devices and systems that perform as a function of engine
          speed, such as in the case of some ignition timing modification and exhaust
          gas recirculation types, the desired test procedure must simulate different
          road speeds to provide complete evaluation of the installed retrofit system.
          Conversely, if the exhaust control technique is independent of road-load
          conditions, then an idle test may be sufficient.  A fundamental requirement
          of any inspection procedure, however, is that it provide a means  of verify-
          ing that the emission reduction potential of a retrofit device is being
          attained within an acceptable tolerance.

     b.   Crankcase Blowby Device Inspection Criteria;  Retrofit crankcase emission
          control systems would be subjected to an operational check and a visual
          component inspection.  These devices may be inspected using crankcase
          vacuum or pressure as a means of establishing failure levels.  A crankcase
          vacuum measurement at idle would provide an objective performance test
          that is more effective than a physical inspection of the system.   This
          would include measuring the crankcase vacuum or pressure and comparing
          it to a rejection level.  For the "open" crankcase systems, the inspection
          criteria would require a crankcase vacuum measurement which would assure
          the inspector that no blowby outflow to the atmosphere is occurring.
          The "closed" or "sealed" crankcase systems criteria could allow some
          crankcase pressure because all crankcase openings are closed to the
          atmosphere.

          Past experience at Olson Laboratories has shown that a crankcase pressure
          of approximately 3 inches of water is acceptable for closed systems without
          any adverse effect on car operation or crankcase system performance.  Most
          closed systems are designed to operate from 1 to 2 inches of water crank-
          case vacuum on a vehicle with average blowby flow rates.

          Detailed procedures for inspecting and measuring the performance of
          crankcase systems are given in California documents. (^-' (2)

     c.   Fuel Evaporative System Inspection Criteria;  Retrofit fuel evaporative
          emission control systems would have to be subjected to visual inspection
          for correct operation and fuel leaks.  The pressure/vacuum safety relief
          system could be inspected with pressure gage instrumentation.

          Quality audits of the vehicle population could be performed using the 1972
          Federal Test Procedure for evaporative emissions.
^  "California Test Procedure and Criteria for Motor Vehicle Crankcase Emission
   Control," California Air Resources Board,  16 August 1966.

   Handbook, Pollution Control Device Installation and Inspection,  HPH 82.1,  Calif-
   ornia Highway Patrol, April 1971.
                                        4-33

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4.3.3.3  Feasibility of Retrofit Inspection and Maintenance

A network of inspection and maintenance facilities to assure that installed devices
and systems are operating as intended would maximize achievement of the emission
reduction goals and objectives of a retrofit program.   Although the feasibility
analysis relative to an inspection and maintenance program for retrofit systems is
beyond the scope of this present study, the factors and tasks that should  be con-
sidered in such an analysis include the following:

     a.   instrumentation and Equipment Required;   This task would identify those
          instruments, equipment, tools, and fixtures required to inspect  and
          service the retrofit device and systems  as installed on the affected
          vehicles.  Initial acquisition costs, service contracts and warranties,
          operating and maintenance manuals, spare parts lists, and other  items
          related to these hardware requirements would be defined.

          Typical instruments would include HC, CO, and NOx analyzers.   Equipment
          would include chassis dynamometers, diagnositic consoles, and vehicle
          lifts, if applicable to the selected inspection procedure.   Tools and
          fixtures may include vacuum and pressure gauges.

          Other requirements are documented test and inspection procedures, service
          and repair procedures for the devices, and any data handling procedures
          and/or computerized programs.

     b.   Technical Personnel Qualifications and Training;   The technical  personnel
          may be categorized into inspection types and maintenance types.   Depend-
          ing on the facility configuration, the inspection and maintenance techni-
          cian may be one and the same.  Personnel qualifications and training
          requirements are dependent on inspection procedures and associated in-
          strumentation relative to a specific retrofit technique.

          The physical installation of the devices evaluated require normal
          automotive mechanic skills.  However, most auto mechanics are not pre-
          sently capable of properly adjusting a retrofit device and related
          engine tuneup parameters for low emissions without some additional
          training.  Technician upgrading with training programs would be  required
          for a successful and effective retrofit  program.

     c.   Facilities Requirements;  Facilities may be privately owned and  operated,
          and regulated through State licensing.  They may also be State owned and
          operated, or State owned and privately operated.   Each alternative
          arrangement has its merits in view of the State,  private industry, and
          the general motorist.

          Inspections may be performed at State facilities  with maintenance per-
          formed by the private sector.  Alternatively both inspections and main-
          tenance may be performed at private facilities.  The economic, social,
          and political implications of each arrangement should be evaluated.
                                        4-34

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4.4  INITIAL AND RECURRING COSTS

4.4.1  Initial Costs

Initial costs are those incurred initially by the vehicle owner in purchasing a retro-
fit device and having it installed as an operating part of the total vehicle.  The
initial costs consist of the material costs and labor costs necessary to provide a
complete retrofit device installation.  Material costs include the basic device it-
self and the accessories that are necessary for a complete installation.  Labor costs
include the time required to accomplish installation, and then to test or adjust the
device for operation.

The number of hours for installation, test, and adjustment was determined by esti-
mating the time required to perform each installation step of the related procedures
(see paragraph 4.5 for installation requirements).  The total time was compared to
the estimate provided by the developer to determine whether there was any significant
difference between the two.  The labor cost was determined by multiplying the standard
California hourly rate of $12.50 by the number of hours.  The estimated retail cost of
the material was taken from the developer's source material, unless this retail cost
was considered unrealistic.  In the latter case, a cost estimate based on historical
cost data for similar items was used.

As part of device installation, most developers required that the engine be "well
tuned"; however, in the retrofit program, the effect and cost of periodic tuneup was
specifically excluded, in accordance with the contract.  Tuneup related costs were
included-only if the developer's installation specified a tuneup related part or
adjustment on which device performance depended.  In this case, the contract exclusion
of tuneup was not considered applicable, since that exclusion was for engine tuneup
when used by itself as a retrofit approach.

4.4.2  Recurring Costs

Recurring costs are those resulting from the upkeep and operation of a retrofit device
during its service life.   These costs include retrofit repair, maintenance, and the
cost of increased or decreased fuel consumption.  The recurring costs are measured in
dollars per mile driven and consist of a summation of the following factors:

     a.   Repair Costs per Mile Driven:   These costs include material and labor
          costs associated with the repair of failed retrofit components.  Math-
          ematically they are calculated from the  mean-time-to-repair (MTTR) in
          hours,  mean-miles-before-partial-failure (MMBPF),  average costs of
          repair parts (C^p), and repair labor rate (L^)  in  dollars per hour.

     b.   Preventive Maintenance Costs;   These costs include material and labor
          costs associated with preventative maintenance which is performed on
          a planned,  scheduled basis to  keep the device in satisfactory oper-
          ating condition.   Mathematically these costs are calculated from the
          mean-miles-before-maintenance  (MMBM),  the mean-time-to-maintain (MTTM)
          in hours,  the  cost  of maintenance parts  (C^p),  and the maintenance
          labor rate  (Lc)  in dollars per hour.

     c.   Fuel  Consumption Cost:   This cost reflects the  increased or decreased
          fuel  consumption resulting from retrofit device operation as a part  of
          the vehicular  system.   This  cost,  in dollars per mile driven,  is computed
                                        4-35

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          from the fuel consumption with the device installed (in gallons per
          mile), fuel consumption without the device installed, and fuel cost in
          dollars per gallon.

Calculation of total recurring costs resulting from the retrofit installation were
based on the figures determined for MMBPF, MTTR, MMBM, MTTM, CRP, and CMP from the
reliability and maintainability data listed in Tables 4-7 and 4-8.  The recurring
cost data were calculated using the equations outlined in Section 3 of Volume
III.

4.4.3  Initial and Recurring Cost Results

The initial and recurring costs calculated for each device are shown in Table 4-9.
The fuel consumption costs were included in the recurring cost calculations for the
devices which were tested in the retrofit program.  It was not possible to include
fuel consumption for those devices which were not tested, because most developers
did not submit fuel consumption data and those who did reported improvements in
economy which were questionable.  The sensitivity analysis summarized in paragraph
3.4 showed that fuel consumption change due to a device installation was the most
sensitive factor influencing recurring costs.

4.5  INSTALLATION AND SKILL LEVEL REQUIREMENTS

The initial step in defining the installation procedure for each retrofit device
was to obtain or develop installation data.  This information had been specifically
requested from the developers, and much of the information 'they provided included
installation procedures on a step-by-step basis.  In many cases, no procedures
were provided but illustrations of installations were available.  Step-by-step pro-
cedures were then developed by comparing the vehicle with and without the device
and determining a logical installation procedure.  In cases where a device was one
of those tested in the retrofit program, the actual installation procedure was used
for comparison purposes.  A list of required material was prepared based on the
installation requirements.  The tools, equipment, instruments, and facilities re-
quired to perform the installation, test, and adjustment procedures were similarly
identified.

Table 4-10 presents a summary of the significant installation and adjustment require-
ments for the retrofit devices studied.

If an emission inspection is required after device installation, then the automotive
mechanic's capability would have to be upgraded to include training in the tech-
nique of emission measurements and adjustments with the appropriate instrumentation.
Paragraph 4.3.3 reviews the inspection requirements for effective retrofit instal-
lations, including instrumentation and facilities.

The implementation of a retrofit emission control strategy requires quality control
of device installations and recurring maintenance and inspections.  Such quality
control would require the regulation of garages and mechanic personnel to verify
their capability to install, adjust, maintain, inspect, and repair the approved
devices.
                                       4-36

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Table 4-9.  INITIAL AND RECURRING COSTS OF DEVICES
                EVALUATED IN RETROFIT PROGRAM


DEVICE
No.



DESCRIPTION
INITIAL COST TO
CAR OWNER


RECURRING COST TO
CAR OWNER
($/100 mir

GROUP 1 EXHAUST EMISSION CONTROL SYSTEMS


62
93
96

292

31
244
463

468

308
425

164

322


1
42
57

325
401
418
433
458
462

10

245
246

294


172
384
430
440

33

56
288
295
317


100
Type 1.1 Exhaust Gas Control Systems:
1.1.1 Catalytic Converter
Catalytic Converter
Catalytic Converter with Exhaust Gas Recirculation,
Spark Modification, and Lean Idle Mixture
Catalytic Converter with Distributor Vacuum Advance
Disconnect
Catalytic Converter
1.1.2 Thermal Reactor
Thermal Reaction by Turbine Blower Air Injection
Rich Thermal Reactor
Rich Thermal Reactor with Exhaust Gas Recirculation
and Spark Retard
Lean Thermal Reactor with Exhaust Gas Recirculation,
1.1.3 Exhaust Gas Afterburner
Exhaust Gas Afterburner
Exhaust Gas Afterburner
1.1.4 Exhaust Gas Filter
Exhaust Gas Filter
1.1.5 Exhaust Gas Backpressure
Exhaust Gas Backpressure Valve
Type 1.2 Induction Control Systems:
1.2.1 Air Bleed to Intake Manifold
Air Bleed to Intake Manifold
Air Bleed to Intake Manifold
Air Bleed with Exhaust Gas Recirculation and Vacuum
Advance Disconnect
Air-Vapor Bleed to Intake Manifold
Air-Vapor Bleed to Intake Manifold
Air Bleed to Intake Manifold
Air-Vapor Bleed to Intake Manifold
Air Bleed to Intake Manifold
Air Bleed to Intake and Exhaust Manifold
1.2.2 Exhaust Gas Recirculation
Throttle-Controlled Exhaust Gas Recirculation with
Vacuum Advance Disconnect
Variable Camshaft Timing
Speed-Controlled Exhaust Gas Recirculation with
Vacuum Advance Disconnect
Exhaust Gas Recirculation with Carburetor
Modification
1.2.3 Intake Manifold Modification
Intake Manifold Modification
Air-Fuel Mixture Diffuser
Induction Modification
Air-Fuel Mixture Deflection Plate
1.2.4 Carburetor Modification
Carburetor Modification, Main Jet Differential
Pressure
Crankcase Blowby and Idle Air Bleed Modification
Carburetor Main Discharge Nozzle Modification
Carburetor with Variable Venturi
Carburetor Modification with Vacuum Advance
Disconnect
1.2.5 Turbocharger
Turbocharger


(3)
(3)
175(5>

73

£<»
(3)

(3)

71
159

103

(3)


64
23
63

56
46
(3)
56
(3)
(3)

71

78
89


(3)

79
(3)
19
12

21

54
41
79
23


(3)


(3)
(3)
0.171<2>

0.047

0.051
0.036
(3)

(3)

0.108
0.059

0.025

(3)


0.022(2)
-0. 191^2)
. 0.062

0.342
0.350
(3)
0.342
(3)
(3)

0.062(2)

0.259"'
-0.040(2)


(3)

0.0
(3)
0.004
0.004

-0.257(2)

0.048
0.144(2)
0.430(2)
0.021


(3)
                        4-37

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Table 4-9.  INITIAL AND RECURRING COSTS OF DEVICES
                EVALUATED IN RETROFIT PROGRAM (CONCL)
DEVICE
NO.
DESCRIPTION
INITIAL COST TO
CAR OWNER
(?)U>
RECURRING COST TO
CAR OWNER
($/100 mi)(4)
GROUP 1 EXHAUST EMISSION CONTROL SYSTEMS (Cont)
22
69
175
23
95
259
268
296
52
459
460
461
464 .
466
182
282
457
465
36
279
1.2.6 Fuel Injection
Electronic Fuel Injection
Type 1.3 Ignition Control Systems
1.3.1 Ignition Timing Modification
Electronic-Controlled Vacuum Advance Disconnect
and Carburetor Lean Idle Modification
Ignition Timing Modification with Lean Idle
Adjustment
1.3.2 Ignition Spark Modification
Electronic Ignition Unit
Ignition Spark Modification
Photocell-Controlled Ignition System
Capacitive Discharge Ignition
Ignition Timing and Spark Modification
Type 1.4 Fuel Modification
1.4.1 Alternative Gas Conversion
LPG Conversion
LPG Conversion with Deceleration Unit
Compressed Natural Gas Dual-Fuel Conversion
LPG Conversion with Exhaust Reactor Pulse Air
Injection and Exhaust Gas Recirculation
Methanol Fuel Conversion with Catalytic Converter
LPG-Gasoline Dual-Fuel Conversion
1.4.2 Fuel Additive
Fuel and Oil Additives
LP Gas Injection
Water Injection
Fuel Additive
1.4.3 Fuel Conditioner
Fuel Conditioning by Exposure to Electromagnetic
Field
Fuel Conditioner
(3)
63
45
(3)
(3)
59
69
23
608
608
601
(3)
(3)
(3)
1
118
(3)
(3)
(3)
16
(3)
0.069(2)
0.332<2>
(3)
(3)
0.025
0.0
0.0
0.021
0.021
(3)
(3)
(3)
(3)
0.293
0.073
(3)
(3)
(3)
0.0
GROUP 2 CRANKCASE EMISSION. CONTROL SYSTEMS
24
170
315
427
160

467

59
165
408
469
Type 2.1 Closed Systems
Heavy Duty Positive Crankcase Control Valve
with Air Bleed
Closed Blowby Control System
Closed Blowby Control System
Closed or Open Blowby Control System with Filter
Type 2.2 Open Systems
Closed or Open Blowby Control System with Filter
34
39
69
68
69
GROUP 3 EVAPORATIVE EMISSION CONTROL SYSTEMS
Fuel Evaporation Control System
137
0.013
0.026
0.038
0.135
0.051

(3) '
• GROUP 4 EMISSION CONTROL COMBINATIONS
Three-Stage Exhaust Gas Control System
Exhaust Gas Af terburner/Recirculation with Blowby and
and Fuel Evaporation Recirculation
Exhaust Gas and Blowby Recirculation with Intake
Vacuum Control and Turbulent Mixing
Rich Thermal Reactor with Exhaust Gas
Recirculation and Particulate Control
(3)
238
36
400
(3)
0.073
0.067
(3)
(1) Estimated retail costs of material and labor excluding engine tuneup costs not related to
device installation.
(2) Device tested in retrofit program.
(3) Insufficient data on which to base cost estimate.
(4) Recurring costs include fuel consumption change as measured during 1972 Federal Test Procedure
for emissions. For devices not tested in retrofit program, recurring costs do not include
fuel consumption effects, as fuel data from the retrofit developers were incomplete generally.
(5) For 8-cylinder engine.
                        4-38

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        Table  A-10.     INSTALLATION  AND  SKILL  LEVEL  REQUIREMENTS   SUMMARY
Mumber                                Installation

EXHAUST GAS CONTROL SYSTEMS

  31     Prill and tap holes in exhau«t  manifold, install turbine blower,  connect
         ;tir  injection nozzles.

  6J     Install  the converter in place  of  the  standard vehicle muffler.   Install
         ,iir  pump to supply auxiliary air to  the converter.   Connect  bypass  to
         system to provide converter overtemperaturo protoction.
                                                                                       Most  Complex Adjustment or
                                                                                                                               Minimum
                                                                                                                             Skill Level
                                                                                  Adjust air  flow to exhaust system for    Automotive Mechanic
                                                                                  Adjust  air  flow volume to converter
                                                                                  for  optimum oxidation of emissions.
         Install converter  in exhmist system.  Install  engine valve timing modl-

         i.'omu-'Ct ;itr pump to converter.
                                                                                 Adjust carburetor  for  lean air-fuel
                                                                                 mixture.   Use  exhaust  analyzer.
         Install catalytic converters, air pump,  and  overheat protection device.
         Remove the  presently installed exhaust system  from the manifold and
         replace with  the exhaust filtering system.
                                                                                  Test overtemperature alarm circuit
                                                                                  during vehicle acceleration and
                                                                                  deceleration.
                                                                                                                         Automotive Mechanic
                                                                                                                         Automotive Mechanic
                                                                                                                         Automotive Mechanic
         install  rtir  pump.


 2Q-2     Install  catalyst e
 308     Install  ;ifterburner in exhaust line,  replace ignition points with dual
         ignition points, install second coil,  hook up afterburner electrically.
 332     Install  spring-controlled flapper  valve  (hinge up) to the end of the
         tail  pipe.
                                                                                 optimum oxidation of emissions.

                                                                                 Adjust carburetor for best lean idle
                                                                                 setting.   Use  exhaust analyzer for


                                                                                 Adjust carburetor air-fuel idle set-
                                                                                 ting to manufacturer's specifications.
                                                                                 Measure available spark voltage to
                                                                                 unit with  engine analyzer.

                                                                                 Insufficient information for adjust-
                                                                                 ment of device.
                                                                                                                         Automotive Mechanic
                                                                                                                         Automotive Mechanic
                                                                                                                         Automotive Mechanic
         Install afterburner unit in exhaust  line, install air pump,  and elec-      Adjust carburetor Idel  air-fuel mix-     Automotive Mechanic
 463     Remove vehicle exhaust manifold  and  replace with the Thermal Reactor.
         For V-8 engines, a reactor is  installed on each cylinder bank.   Connect
         re;ictors to vehicle exhaust system.  Connect EC.R diaphragm valve to  the
         vacuum advance line.   Connect  EGR  valve inlet to exhaust system.   ECR


 668     Insufficient data.
INDUCTION  CONTROL SYSTEMS

   1     Install adapter plate between  carburetor and intake manifold,  mount
        va Ive body assembly in engine  compartment, and connect va Ive body  to
        adapter plate.
  10      Install adapter plate between carburetor and intake manifold.   Replace
         inner venturi in carburetor  with vaporizer.  Connect reclrculating  tube


  >2      Insufficient data.
33     Drill  holes  in  top of carburetor fuel bowl  and  in  Intake manifold.  Con
       nect  these holes with hose that includes  a  vacuum  adjustment valve.


42     Drill  holes  in  intake manifold and air filter casing.  Install con-
       nectors  and  hook up device with hose.

56     Replace  idle mixture screws with special  screws, install adapter plate
       between  carburetor and intake manifold, mount vacuum switch and heater
       assembly on  carburetor, connect hoses and wiring.


57     Install  adapter plate between carburetor  and intake manifold.  Install
       vacuum disconnect switch and vacuum hoses.
                                                                                                                         Automotive Mechanic
                                                                                 ture to  11.5:1.  Use exhaust analyzer.

                                                                                 Adjust exhaust recycle gas to 12 per-
                                                                                 cent of  engine intake air.  Adjust air
                                                                                 flow to  converter for optimum emission
                                                                                 reduction  - use exhaust analyzer.
                                                                                 Adjust spark advance for  low emissions   Automotive Mechanic
                                                                                 and acceptable driveabllity.
                                                                                                                        Automotive Mechanic
                                                                                 Balance  idle air-fuel mixture screws
                                                                                 to  obtain smoothest idle at recom-
                                                                                 mended speed.  Adjust for combustion
                                                                                 efficiency of 75-80 percent.   Unscrew
                                                                                 device counterweight for 1-3" Hg vacu-
                                                                                 um  reduction In intake manifold vacuum.
                                                                                 Readjust counterweight to increase  com-
                                                                                 bustion efficiency above 85 percent.(I)

                                                                                 Adjust carburetor for best idle air
                                                                                 fuel mixture using exhaust analyzer.


                                                                                 Insufficient information for  device
                                                                                 adjustment.

                                                                                 Adjust device valve during steady
                                                                                 cruise until noting a drop in engine
                                                                                 rpm.  Close valve slightly and lock.

                                                                                 Adjust the device valve with  a CO
                                                                                 exhaust analyzer.

                                                                                 Test vacuum switch and heater elements   Automotive Mechanic
                                                                                 for function.  Adjust carburetor Idle
                                                                                 air-fuel mixture for best lean opera-
                                                                                 tion.  Adjust idle rpm with tachometer.
                                                                                                                         Automotive Mechanic
                                                                                                                         Insufficient  Info.
                                                                                                                         Automotive Mechanic
                                                                                                                         Automotive Mechanic
100     Install  turbocharger  in new exhaust system.   Turbocharger  intake air is

        venturi  inlet.   Install electric fuel pump for  high  boost  operation.

172     Remove intake manifold from engine and insert device into  manifold.
        Reinstall manifold.   Install leaner primary  jets  in  carburetor.
                                                                                 Automatic transmissions - adjust idle
                                                                                 50 rpm over  manufacturer's recoromenda-

                                                                                 idle 75 rpm  over manufacturer's recom-
                                                                                 mendations.   Adjust  carburetor idle
                                                                                 mixture to 86 percent combustion ef-

                                                                                 carbon monoxide.   Idle 2200 rpm adjust

                                                                                 efficiency or 1.2  ±0.1 percent carbon
                                                                                 monoxide.(1)

                                                                                 Insufficient  information.
                                                                                                                         Automotive  Mechanic
                                                                                                                         Automotive  Mechanic
                                                                                Adjust engine idle rpm to manufactur-    Automotive Mechanic

                                                                                retor for best lean idle  mixture.
                                                                  4-39

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        Table  4-10.     INSTALLATION  AND  SKILL  LEVEL  REQUIREMENTS  SUMMARY  (CONT)
 Device
 Number
                                      Installation

 INDUCTION CONTROL SYSTEMS (Cont)

  245     Replace valve cam timing sprocket with a new variable cam sprocket.
  246     Install adapter  plate  between carburetor and  Intake manifold.  Connect
         rcclrculatlng tube  from exhaust to vacuum-operated shutoff valve to
         adapter plate.   Install solenoid valve.   Replace  speedometer cable with
         new one having switch  installed.

  288     Remove venturi assembly from carburetor  and  install device into assem-
         bly.  Reassemble into  carburetor.
          Insufficient information  for  installation of the device.
                                                                                      Most Complex Adjustment  or
                                                                                      	Test Characteristic
                                                                                  Adjust basic  Ignition timing to manu-
                                                                                  facturer's  specifications.  Adjust
                                                                                  carburetor  idle air-fuel mixture for
                                                                                  lean operation using exhaust analyzer

                                                                                  Adjust carburetor for beat lean Idle
                                                                                  setting.  Use exhaust analyzer for
                                                                                  optimum emissions reduction.
                                                                                  Adjust idle  rpm and adjust carburetor
                                                                                  for best idle air-fuel mixture with
                                                                                  exhaust analyzer.
                                              Minimum
                                            Skill Level
                                                                                                                          Automotive Mechanic
                                                                                                                         Automotive Mechanic
                                                                                                                          Automotive Mechanic
                                                                                  Insufficient  information for adjustment   Insufficient Info.
                                                                                  of device.    •          :
  295      Remove carburetor and replace with new variable venturi  carburetor.
  317     Replace carburetor primary metering jet, insert capillary  tube in
         carburetor cover,  connect evaporation chamber to PCV valve.
 325/    Mount a  fluid  reservoir in the engine compartment, install adapter
 433     plate between  carburetor and intake manifold, replace idle adjusting
         screws with  special screws, and connect hose  from reservoir to adapter
         plate.        •

 384     Remove carburetor and install device in Intake manifold.  Replace
         carburetor.
 401     Mount fluid  reservoir in engine compartment,  insert T-fitting in PCV
         hose, connect reservoir to T-titting.

 418     Insert the device In the crankcase ventilation return line between the
         PCV valve and Intake manifold.

 430     Remove carburetor and install device in  intake manifold.  Replace-
         carburetor.
 460     Install device between carburetor and intake manifold.
 458     Install  fluid reservoir on fender  wall.  Insert vapor metering T-valve
         in  crankcase ventilation return line between PCV valve and intake mani-
         fold.  Connect reservoir outlet tube to  the T-valve.  Fill reservoir
         with  fluid.

 462     Connect  exhaust scavenger to the tapped  holes in the exhaust manifold.
         Install  the crankcase scavenger in the positive crankcase line.  Remove.
         the interior part of the PCV valve.

IGNITION CONTROL  SYSTEMS

  23     Insufficient information for Installation of the device.
Adjust throttle linkage  to  carburetor.
Readjust Idle rpm and  idle  air-fuel
mixture for best lean  operation.

Readjust basic ignition  with elec-
tronic engine analyzer.   Set carbu-
retor air-fuel mixture to 15:1.  Reset
carburetor choke 1 division (rich)
from factory specifications.

Readjust idle rpm and  idle  air-fuel
mixture.  Observe with engine running
that device is aerating  and that all


Adjust carburetor idle air-fuel mix-
ture.  Use multimeter  to check for
device "shorts."

Adjust idle rpm.  Adjust valve for
flow of air through device  intake.

Adjust carburetor idle air-fuel mix-
ture.  Use exhaust analyzer.

Adjust Idle automatic  transmission to
620 rpm.  Standard transmissions to
700 rpm.  Adjust carburetor to minimum
HC and CO level on exhaust  analyzer.
Adjust automatic choke to lean value.

Adjust engine Idle rpm and  carburetor
air-fuel mixture.  Use exhaust
analyzer.

Adjust carburetor Idle air-fuel mix-
ture.  Use exhaust analyzer.
                                                                                                                          Automotive Mechanic
                                                                                                                          Automotive Mechanic
                                                                                                                         Automotive Mechanic
                                                                                                                         Automotive Mechanic
                                                                                                                          Automotive Mechanic
                                                                                                                         Automotive Mechanic
                                                                                                                          Automotive Mechanic
                                                                                                                         Automotive Mechanic
                                                                                                                         Automotive Mechanic
                                                                                  Insufficient information for adjust-     Automotive Mechanic
                                                                                  ment  of  the device.
                                                                                  Insufficient Information for adjust-
                                                                                  ment of  the device.
                                                                                                                          Insufficient Info.
  69     Install the spark retard device,  solenoid valve in vacuum advance  line.
         and replace idle adjust screws.
         Install control unit in engine  compartment, hook up wiring and  vacu
         hose  to distributor and coil.
        Replace points and condenser  In distributor with photocell and  shadow
        disc.  Install amplifier coil in  engine compartment.  Make wiring
        connections .

        Install unit  in engine compartment and connect wires.

FUEL MODIFICATION SYSTEMS

  36     Install the device In the fuel line between  the  fuel pump and the car-
         buretor.  Connect terminals (electrical)  to  12-volt dc supply.

  52     Install converter and fuel filter plus  vacuum  fuel lock unit.  Connect
         heater water  to converter.  Connect vacuum fuel  lock to Intake manifold.
         Install Type  C carburetor adapter and  carburetor on Intake manifold.
         Install 160°F thermostat In engine cooling system.  Install 35-gallon
         LPG  tank set, wire braid hoses,  fuel gage, and remote fill Line.
                                                                                  Adjust  ignition timing control for  low   Automotive Mechanic
                                                                                  speed engine performance.  Adjust car-
                                                                                  buretor air- fuel for minimum emission
                                                                                  levels  at  idle rpm and trim adjustment
                                                                                  at  1,600 rpm,

                                                                                                                         Automotive Mechanic
                                                                                  engine analyzer.

                                                                                  Adjust engine Idle rpm and Idle air-
                                                                                  fuel mixture (exhaust analyzer).   Ad-
                                                                                  just unit for proper solenoid switch
                                                                                  operation with engine analyzer.

                                                                                  Adjust basic ignition timing and  test    Automotive Mechanic
                                                                                  spark voltages with electronic engine
                                                                                  analyzer.
                                                                                  Readjust dpark plug gap and adjust
                                                                                  basic  ignition timing with electronic
                                                                                  engine analyzer.
                                                                                                                         Automotive Mechanic
                                                                                  engine analyzer.
                                                                                 Insufficient information.
                                                                                                                         Automotive Mechanic
                                                                                 Adjust idle air-fuel  mixture.  Test      Automotive Mechanic
                                                                                 for leaks.  Adjust power  mixture at
                                                                                 wide open throttle.
                                                                   4-40

-------
       Table  4-10.     INSTALLATION  AND  SKILL  LEVEL  REQUIREMENTS  SUMMARY  (CONCL)
 Numbgr                               Installation

 FUEL MODIFICATION SYSTEMS  (Cont)

  182     Fuel additive;  no Installation required.
                                                                                      Most Complex Adjustment  or
                                                                                         Test Characteristic
                                                                                                                             Skill  Level
                                                                                 Check condition of fuel  filter.  Re-     Vehicle owner
                                                                                 place as neceasary.
  279     Mount the device  in  the engine compartment  and  connect It into the fuel    Check system for electrical  leaks, or    Automotive  Mechanic
         line between fuel pump and carburetor.   Connect electrical wiring.        shorts,

  282     Mount LPG tank in trunk of car, mount regulating valve assembly,  connect   Adjust setting of regulating valve to    Automotive  Mechanic
         with copper tubing from tank to valve to intake.                          minimize ignition spark knock  (ping-
                                                                                 ing).  Check system for leaks.

  457     Insufficient Information.                                                Insufficient information                Insufficient  Info.

  459     Insufficient information.                                                Adjust fuel flow valve and air flow      Automotive  Mechanic
                                                                                 valve drag linkage.

  460'    Install pressure  regulators on left front side  of engine compartment.      Adjust final pressure for  light  load     Automotive  Mechanic
         Install mixer on  carburetor.  Install connector and fuel filter plus       operation.  Adjust mixer idle  screw
         vacuum fuel lock  unit.  Connect heater  water  to converter.  Connect       to lean drop-off point.
         vacuum fuel lock  to  intake manifold.   Install 160°F thermostat In en-
         gine cooling system.  Install CNG tanks, fuel lines, solenoid valves
         and Bowden control cable.

  461     Insufficient information.                                                Insufficient information.                Insufficient  Info.

  464     Install carburetor modification kit for conversion of gasoline fuel to     Adjust carburetor for air-methanol       Automotive  Mechanic
         methanol.   Install converter close as possible  to exhaust manifold.       (fuel) mixture.
         Install air pump  and connect air supply to  converter.

  465     Fuel additive;  no installation required.                                 Insufficient Information available for   Insufficient  Info.
                                                                                 preparation of additive-treated  fuel.

  466     Install converter and fuel filter plus  vacuum fuel lock unit.  Connect     Adjust Idle air-fuel mixture.  Test      Automotive  Mechanic
         heater water to converter.  Connect vacuum  fuel lock to intake manifold.   for  leaks.  Adjust power mixture at
         Install Type C  carburetor adapter and carburetor on intake manifold.       wide open throttle.
         Install 160°F thermostat in engine cooling  system.  Install tank set,
         hoses, fuel gage  and remote fill line.

CRANKCASE EMISSION CONTROL SYSTEMS

  24     Replace PCV valve with variable jet valve.  Install separator unit in      Check crankcase pressure (or vacuum)     Automotive  Mechanic
         blowby line between variable jet valve  and  the  crankcase.                 after installing device.

  160     Mount filter unit in engine compartment, install hose adapter fittings.    Readjust carburetor for best lean idle   Automotive  Mechanic
         and connect hoses.                                                       air-f uel mixture.  Set id le  rpm  to
                                                                                 manufacturer's specifications.

  170     Replace PCV valve with a special valve,  connect hoses, plug and seal       Adjust device metering valve to obtain   Automotive  Mechanic
         all outlets to  the crankcase.                                             4-5" Hg vacuum at idle rpm.  Readjust
                                                                                 carburetor to obtain best  idle rpm and
                                                                                 Idle air-fuel mixture.  Use  exhaust
                                                                                 analyzer.

  315     Replace PCV valve with an adjustable  flow control valve.   Connect con-     Adjust control valve to maintain vacu-   Automotive  Mechanic
         trol valve linkage to accelerator pedal  Linkage.  Replace oil fill cap.    urn of 0.5 inch Hg at valve cover.  Re-
         Install adapter plate between  carburetor and  intake manifold.             adjust carburetor for best Idle air-
                                                                                 fuel mixture - use exhaust analyzer.
                                                                                 Set  idle rpm.

 427     Mount the  filter  unit in the engine compartment, replace PCV valve with    Adjust carburetor for best lean opera-   Automotive  Mechanic
         special part, connect to filter unit.                                     tion.  Use exhaust analyzer.  Set idle
                                                                                 rpm.
EVAPORATIVE EMISSION CONTROL SYSTEMS

 467     Replace existing  gas tank with a sealed  gas tank; install vapor sepa-      Insufficient Information                Automotive  Mechanic
         rator, carbon canister,  connecting tubing,  three-way check valve, check
         valve, and miscellaneous hoses, clamps,  and connectors.

COMBINATIONS

  59     Insufficient  Information                                                 Insufficient Information                Insufficient  Info.

  165     Install afterburner in exhaust line,  connect  afterburner to Intake, con-   Regulate the flow of exhaust gases       Automotive  Mechanic
         nect fuel  tank  emission accumulator to  intake,  connect crankcase  emission  through the afterburner and  the heat
         to Intake,  install high  voltage coil, glo plug, flow control valves,       exchanger.  Adjust to give best  over-
         filter.                                                                  all  engine performance.
408     Install  an adapter plate between the  carburetor and intake manifold.
        Correct  recirculatlng line from exhaust  line to adapter plate.   Connect
        PCV valve to adapter plate.  Replace  oil filter cap with check valve
        oil-fill cap.
         Insufficient information.
                                                                                 Adjust acceleration valve  for minimum    Automotive Mechanic
                                                                                 exhaust gas inlet at 21" Hg vacuum at
                                                                                 idle.  Adjust deceleration valve  to
                                                                                 open at 25" Hg vacuum during
                                                                                 deceleration.  ,
                                                                                  Insufficient informatio
                                                                                                                         Insufficient Info.
 (I)  "Combustion efficiency" refers to the  calibration used on some engine analyzers for adjusting the air-fuel  ratio.
                                                                   4-41

-------
In general, the emission reduction benefit of a retrofit device on an assured
basis would require some form of emission test following installation and upon
repair action to the device.  These requirements for quality control predicate a
qualified mechanic skill level, knowledgeable in retrofit device operating prin-
ciples and in the use of equipment and instrumentation capable of verifying that
a device is functioning properly.  The management of a regulated quality control
system further predicates qualified inspection personnel to train and certify
mechanics for participation in a retrofit program.

The type of quality control program required to implement and sustain use of retro-
fit devices is illustrated by that used in California for the installation, adjust-
ment, servicing, inspection, and certification of vehicle pollution control equip-
ment. (1)   This California program prescribes specific inspection requirements to
be followed in the certification of emission controlled vehicles upon change of •
ownership.   Inspection stations are licensed by the State, and a Class A pollution
control device installer certification is required  of inspection personnel.  A
Class A installer has to be experienced in major automotive tuneup, with optional'
instruction from an approved school.   Applicants must pass an examination before
certification is granted.  Quality controls of equivalent stringency are con-
sidered essential requirements of any program based on use of retrofitted vehicle
emission control devices as a means of achieving air quality standards.
(1)   Handbook for Pollution Control Device Installation and Inspection,  HPH 82.1
     California Highway Patrol,  April 1971.
                                       4-42

-------
5 - PERFORMANCE
    ANALYSIS

-------
                                     SECTION 5

                                PERFORMANCE ANALYSIS


 By means of the methodology described in Section 3,  an analytical  evaluation was made
 of those devices for which sufficient data were developed  through  engineering analy-
 sis and test.  The objective was to determine  the relative index ratings  of the de-
 vices in terms of their effectiveness in reducing vehicle  emissions,  effect on
 vehicle performance, and costs to the vehicle  owner.

 Data for the evaluation were obtained through  the data survey  or by test.  These were
 reviewed for acceptance in the engineering analysis  of the retrofit devices.  The
 completeness of data provided by the retrofit  data survey  varied widely.   The emission
 test data provided by the developers were nearly always supported  by  a  test report
 from a recognized independent test facility.   Reliability, maintainability, and cost
 data were evaluated for reasonableness,  and supplemented or complemented  by analysis
 when sufficient system information was available.  Driveability data  were  for the
 most part incomplete, because of the lack of data on baseline  vehicle driveability.
 Fuel consumption data were generally not provided.   Therefore, driveability and fuel
 consumption evaluation was made only on  those  devices tested in the retrofit program.

 Eleven devices were tested for emission  reduction, fuel consumption,  and  driveability.
 Four of these devices were selected for  more extensive emission, fuel consumption,
 and driveability testing to obtain data  samples from a variety of  used  cars in two
 different geographic areas of the U.S.,  as described  in Section 4.  Table  5-1 summa-
 rizes all of the available performance data of the devices that were  tested and the
 devices that received an engineering evaluation based on data  supplied  by  the
 developer.

 5.1  CRITERIA INDEX

cThe Criteria Index measures the ability  of a device  to meet  legal  constraints and
 specified limits that could be imposed for critical performance parameters.  Values
 for the various Criteria Index factors were assigned  1 or  0  depending on whether or
 not the evaluation criteria presented in Table 1-2 were satisfied.  In  all cases,
 inadequate  data supplied by the developers prevented  complete  Criteria  Index evalu-
 ations of the devices.   As a result,  the Criteria  Index could  be established only
 for some devices.   Certain devices  were  found  to have a value  of 0 for  at  least one
 of  the criteria index factors.   In  these cases the Criteria  Index was also 0, since
 this  index  is the  product  of the individual factors.

 In  the retrofit test program,  CVS tests  were conducted under the 1972 Federal Test
 Procedure,  for which no used car emission standards had been established at the
 time  of this study.   Therefore, the emission standard criteria of  the Criteria Index
 could not be applied to the 1972 CVS  test data,  and  the Criteria Index  could not be
 established for these cases.
                                        5-1

-------
Table 5-1.   PERFORMANCE  SUMMARY OF  DEVICES  EVALUATED IN RETROFIT  PROGRAM
             NOTE;  THE RELIABILITY OF THE DATA SHOWN DEPENDS ON THE TYPE OF TEST PROCEDURE AND THE NUMBER OF TESTS.
DEVICE
NO.

,6<«
175
246

10
33
42
69
245
288
295

23
24
52
93
95
100
292
294
MS •
460

462
463
464
465
466
468
469


31
36
56
57
59
f>2
160
182
244
315
317
DESCRIPTION
Devices with up to 18 Tests In Retrofit
Air Bleed to Intake Manifold
Catalytic Converter with Distributor
Vacuum Advance Disconnect
Iginition Timing Modification with Lean
Idle Adjustment
Speed-Controlled Exhaust Gas Recircula-
tion with Vacuum Advance Disconnect

Throttle-Controlled Exhaust Gas Reciru-
lation with Vacuum Advance Disconnect
Carburetor Modification, Main Jet
Air Bleed to Intake Manifold
Electronic-Controlled Vacuum Advanre
Modification
Variable Camshaft Timing
Carburetor Main Discharge Nozzle
Modification
Carburetor with Variable Venturi
Devices Evaluated Based on Developer and
Electronic Ignition Unit
Heavy Duty Positive Crankcase Control
Valve with Air Bleed
LPG Conversion
Catalytic Converter with Exhaust1 Gas
Lean Idle Mixture
Ignition Spark Modification
Turbocharger '
Catalytic Converter
Exhaust Gas Recirculation with
Air Bleed to Intake Manifold
Unit
Compressed Natural Gas Dual-Fuel
Conversion
Pulse Air Injection and Exhaust Gas
Air Bleed to Intake and Exhaust
Manifold
Rich Thermal Reactor with Exhaust Gas
Recirculation and Spark Retard
Methanol Fuel Conversion with Catalytic
Converter
Fuel Additive
LPG-Gasoline Dual-Fuel Conversion
Lean Thermal Reactor with Exhaust Gas
Recirculation
Rich Thermal Reactor with Exhaust Gas


Thermal Reaction by Turbine Blower Air
Injection
Fuel Conditioning by Exposure to
Electromagnetic Field
Crankcase Blowby and Idle Air Bleed
Modification
Air Bleed with Exhaust Gas Recirculation
and Vacuum Advance Disconnect
Three-Stage Exhaust Gas Control System
Catalytic Converter
Closed or Open Blowby Control System
with Filter
Fuel and Oil Additives
Rich Thermal Reactor
Closed Blowby Control System
Carb Mod with Vac Adv Disconnect
CRITERIA
INDEX
Program (1
(1)
0
0
0
ogram (197
(1)
0
(1)
(1)
0
0
0
EPA Data:
0
(1)
0
(1)
0
(1)
0
0
(1)
0

0
(1)
CD
(1)
(1)
(1)
(1)


0
0
0
0
0
0
(1)
0
0
0
0
NUMBER
OF
TESTS
)72 Fede
ie
17
10
15

2
2
2
3
]
2
1

1
(8)
18
fi
1
I
1
1
(9)
1

(21)
3
6
1
6
5
2


6
(ID
3
1
1
1
1
(12)
(10)
1(13)
3
AVERAGE
EMISSION
INDEX
PER UNIT<2>
REDUCTION
ral Test Proc
0.247
0.596
- 0.343
0.302

0.396
0.118
0.237
0.287
-0.139
0.074
0.028

-0.231
0.079
0.771
(10)
-0.251
0.113
0.156
-0.128
0.165
-0.277

0.024
(10)
(10)
0.101
0.393
(10)
0.630


(10)
-0.065(13)
(10)
0.516
0.204
0.218
(10)
0.269
0.750(13)
0.281
0.297
AVERAGE
DRIVE ABILITY
INDEX
RATING
POINTS
sdure) :
0.138
0.304
0.118
0.113

0.441
0.181
0.116
0.087
0.895 '
-0.459
3.261(20

(10) (6)
(10)
(10)
(10)
(10)
(10)
(10)
(10)
(10)
(10)

(10)
(10)
(10)
(10)
(10)
(10)
(10)

(10)
(10)
(10)
(10)
(10)
(10)
(10)
(10)
(10)
(10)
(10)
(10)
COST INDEX
S/100 MILESO)

0.063
0.521
0.391
0.079

0.204
-0.229
-0.161
0.152
0.364
0.198
0.536

(10)
0.047
0.224
(10)
(10)
(10)
0.192
(10)
(10)
(10)

(10)
(10)
(10)
(10)
(10)
(10)
(10)


0.337
(10)
0.120
0.188
(10)
(10)
0.143
(10)
0.536
0.175
0.052
PERFORM-
ANCE
ITOEX(4)

0.103
0.163
0.067
0.134

0.105
0.174
. 0.165
0.110
-0.312
0.054
-0.603

(10) (7)
(10)
(10) .
(10)
(10)
(10)
(10)
(10)
(10)
(10)

(10)
(10)
(10)
(10)
(10)
(10)
(10)

(10)
(10)
(10)
(10)
(10)
(10)
(10)
(10)
(10)
(10)
(10)
(10)
COST
EFFECTIVENESS
INDEX,
UNIT REDUCTION
S/100 MILES

3.92
1.14
0.88
3.82

1.94
-0.51 (18)
-1.47 (18)
1.89
-0.38 (19)
0.37
0.05

(10)
1.68
3.44
(10)
(10)
(10)
0.81
(10)
(10)
(10)

(10)
(10)
(10)
(10)
(10)
(10!
(10)

(10)
(10)
(10)
(10)
2.74
(10)
(10)
(10)
0.19
(10)
1.39
(10)
5.71
INITIAL
COST FOR
INSTAL-
LATION
$

64
175
45
89

71
21
23
61
78
41
79

(10)
34
608
(10)
(10)
(10)
73
(10)
(10)
601

(10)
(10)
(10)
(10)
(10)
(10)
400

(10)
143
(10)
54
63
(10)
(10)
69
103
1
375
69
23
TEST
TYPE





972 FEDERAL TJ
3
RDCEDURE (CVS)






X
CoS
l/l

o
s
K
§
S
8
B
n

(16)
DATA
SOURCE

R
R
R
R

R
R
R
R
R
R
R

E
E
E
E
E
E
E
E
E
E

E
E
E
E
E
D
E

E
D
E
D
D
D
E
D
D
D
D
D
D
                                            5-2

-------
 Table 5-1.  PERFORMANCE  SUMMARY OF DEVICES EVALUATED IN RETROFIT PROGRAM (CONCL)
NOTE: THE RELIABILITY OF THE DATA SHOWN DEPENDS ON THE TYPE OF TEST PROCEDURE AND THE NUMBER OF TESTS.
DEVICE
NO.
322
384
401
425
430
438
165
170
279
296
325
427
433
308
457
268
282
408
440
467
DESCRIPTION
Exhaust Gas Backpressure Valve
Air-Fuel Mixture Dlffuser

Induction Modification
Air Bleed to Intake Manifold
with Blowby and Fuel Evaporation
Reclrculation
Closed Blowby Control System
Fuel Conditioner
Ignition Timing and Spark Modification
Air-Vapor Bleed to Intake Manifold
Closed or Open Blowby Control System
with Filter
Air-Vapor Bleed to Intake Manifold
Exhaust Gas Afterburner
Uater Injection
Capacltive Discharge Ignition
LP Gas Injection
Exhaust Gas and Blowby Recirculatlon with
Intake Vacuum Control and Turbulent
Mixing
Air-Fuel Mixture Deflector Plate
Fuel Evaporation Control System
CRITERIA
INDEX
0
0
0
0
0
0
0
0
0
(1)
0
(I)
0
0
(1)
(1)
(1)
0
0
(1)
' 0
NUMBER
OF
TESTS
1
1
1
1(13)
2
(15)
1
1
1
1
7
2
7
3(14)
(14)
(10)
(10)
(10)
(10)
(10)
(10)
AVERAGE
EMISSION
INDEX
PER UNIT(2)
REDUCTION
-0.258
0.297
0.094
0.970
0.267
-0.016
(10)
0.087
0.107
0.027
0.239
0.182
0.239
-0.047
0.250
(10)
(10)
(10)
(10)
(10)
(10)
(1) Criteria Index not totally determined due to lack of emission standards
(2)
(3)
t
(4) 1
(5) >
c
(6) h
I
(7)
(8) 6
t
(9) 1
(10) I
(11) 1
ndlvldual Criteria Index parameter evaluations.
egatlve sign indicates emission increase from baseline.
egatlve sign indicates cost saving due to more miles per gallon with
evlce installed.
o lead gasoline at $0.38/gallon. For the other devices, gasoline cost
alculated on basis of $0.35/gallon.
riveability Index not determinable for thl
PI not determinable due to lack of DI's for
baseline and 5 device tests for HC and CO
eats for NOx.
nknown
baseline test, and 11 device teats for HC
B or subsequent devices.
this and subsequent devices
3 baseline and 4 device
ara.
and CO only.
AVERAGE
DRIVEABILITY
INDEX
RATING
POINTS
(10)
(10)
(10)
(10)
(10)
(10)
(10)
(10)
(10)
(10)
(10)
(10)
(10)
(10)
(10)
(10)
(10)
(io)
(10)
(10)
(10)
(12)
• (13)
(14)
(15)
(16)
(17)
(18)
(19)
(20)
(21)
COST INDEX
$/100 MILES (3)
(10)
(10)
0.442
0.377
0.030
(10)
0.549
0.065
0.033
0.031
0.454
0.271
0.454
0.250
(10)
0. 104
0.046
0.309
0.139
0.020
(10)
PERFORM-
ANCE
INDEX(4)
(10)
(10)
(10)
(10)
(10)
(10)
(10)
(10)
(10)
(10)
(10)
(10)
(10)
(10)
(10)
(10)
(10)
(10)
(10)
(10)
(10)
COST
EFFECTIVENESS
INDEX
UNIT REDUCTION
S/100 MILES
(10)
(10)
0.21
2.57
8.90
(10)
(10)
1.34
3.24
0.87
0.53
0.67
0.53
-0.19(19)
(10)
(10)
(10)
(10)
(10)
(10)
(10)
4 tests for HC and CO; 1 teat for NOx.
HC and CO only.
1 baseline and 2 device tests on 1 car.
D - Developer Supplied Data
INITIAL
COST FOR
INSTAL-
LATION
$
(10)
(10)
46
159
19
(10)
238
39
16
23
56
68
56
71
(10)
59
69
118
36
- 12
137
TEST
TYPE
n9r
MS
1 =
8
7-CYCLE 7-MODE HOT
START
W (/>
™S~|
a
(/)
H
1

(16)
DATA
SOURCE
E
D
D
D
D
E
D
D
D
D
D
D
D
D
E
D
D
D
D
D
(10)

EPA Interim 9-Cycle, 7-Mode CVS Emission Test Procedure (refer
to Volume II, Reference 16).
gallon of fuel.
above baseline.
Validity of thla driveabillty test doubtful (see Table 4-6).
10 baseline and 9 device tests for HC and CO, and 6 baseline
and 6 device teats for NOx, on 2 cara.
Section 3 of Volume III presents a discussion of the individual Criteria Index
factors.

5.2  PERFORMANCE INDEX

The Performance Index (PI) measures the relative performance rating of the devices
and enables a further quantitative refinement beyond the Criteria Index, which is a
qualitative evaluation.  The devices are listed in Table 5-1 in terms of emission
reduction, driveability, and cost indexes.   The negative values shown in Table 5-1
for the Emission Index indicate an overall  increase in the emission levels as a re-
sult of device installation.  The highest positive numerical Emission Index value
represents the greatest ability to control  (or reduce) emissions.  The percentage
reductions for the individual pollutants achieved by each device are listed in
Table 4-2.

Note that all reported emission indexes were not obtained using the same testing
procedures, nor the same number of tests.  This should be kept in mind when judging
the relative significance of the data.
                                        5-3

-------
The Driveability Index, an indication of a penalty, becomes numerically smaller as
the driveability penalty becomes less.  Negative values indicate an improvement in
vehicle driveability with the device installed.  The devices are relatively worse
as their index values increase.  The developers of devices that were not tested in
the retrofit program were generally unable to provide driveability data because of
the lack of information on their own test vehicles prior to device installation.

The Cost Index combines those parameters which determine the initial costs of a
device and the recurring costs.  The initial costs are measured in terms of device
retail cost and installation cost amortized over the device lifetime.   The recur-
ring costs, such as maintenance and gasoline mileage changes,  are added expenses
for keeping the retrofit device in operation after installation.

Negative values for the Cost Index represent a cost savings attributable to
increased gasoline mileage.   Devices are rated relatively worse as their Cost Index
values increase, since increased cost is a penalty.

The Performance Index provides the overall performance rating of devices for which
Emission,  Driveability,  and  Cost Indexes could be calculated.   The set of weighting
factors used in this analysis rate emissions twice as important as cost and cost is
rated twice as important as  driveability.  Other weighting factors may be used as
described in paragraph 3.4 and Table 6-13 of Volume III.

5.3  COST EFFECTIVENESS INDEX

The Cost Effectiveness Index (CEI) is intended to provide additional information to
complement the Performance Index.  Should two or more devices have essentially the
same Performance Index, the one with the highest Cost Effectiveness Index would be
preferred.  Cost Effectiveness is usually defined as the rate of the desired results
or the desired output versus the required cost input.  In this discussion, the CEI
is defined as the ratio of the Emission Index to the Cost Index.

A thorough comparative analysis of devices by the evaluator should incorporate and
review the absolute Emission and Cost Indexes along with the Performance and Cost
Effectiveness Indexes.  The reason for this is that the pure CEI ratio  (by itself)
will not reveal the difference between two devices that have different absolute
Emission and Cost Indexes.  The evaluator must question the merits of a device to
fit his requirements.  He must ask "How much emission reduction do I need to fit
my requirements, and how much money will it cost for that reduction?"  Once he has
these questions answered, he may then compare devices by reviewing the PI.

Negative values for the Cost Effectiveness Index are obtained for two reasons:

     a.  A cost savings was achieved due to better fuel economy.   This  is indicated
         by a negative Cost Index.

     b.  An overall increase in emissions was achieved.  This is indicated by a
         negative Emission Index.

The first case is clearly favorable, while the second case would mean spending
money to increase emissions.
                                        5-4

-------
For positive Cost Effectiveness Index values, the higher numbers indicate the larger
emission reductions per dollar.

5.4  FEASIBILITY

The feasibility and infeasibility of a retrofit device, within the context of this
study, can only be determined with respect to the device's applicability for use as
a retrofit method for controlling vehicle emissions.  A device may be rated infeas-
ible for emission control without infringing upon its use for other applications.
For example, some devices, while being claimed as emission reduction devices, actu-
ally are devices for enhancing some engine performance parameter that only indirectly
or insignificantly reduces emissions.  Any additional claims made for a device by the
developer are not considered here, because the findings of this study pertain bnly
to a device's use as a retrofit method to control vehicle emissions effectively and
without unacceptable vehicle performance and cost penalties.

To determine which devices are feasible and which are not, the evaluation criteria
presented in Table 1-2 can be applied.  These criteria can be changed to fit the
specific requirements of the particular air quality control agency.  In effect,
the evaluation criteria determine the feasibility or infeasibility of a device.
Those devices that passed the evaluation criteria levels would be the feasible
retrofit systems and the rest may be infeasible to some degree.

It should be mentioned that most of the devices evaluated in this study are prototype
systems.  In some cases, sound engineering and manufacturing techniques may remove
the reasons for device infeasibility.
                                       5-5

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6 - DEVELOPMENT STATUS
    AND APPLICABILITY

-------
                                    •  SECTION  6

            RETROFIT  DEVICE  DEVELOPMENT  STATUS AND VEHICLE APPLICABILITY


 Ultimately,  the  feasibility of  a retrofit device for control  of used  car emissions
 depends  on  its development  status  and the extent to which it  is applicable  to  the
 vehicle  population which must be controlled.  A device may  theoretically and
 experimentally indicate substantial emission  reduction effectiveness  at an  accept-
 able  cost and yet require too long a  period of development  to be  producible for
 mass  application.  Developmental requirements may be compounded by accreditation
 requirements.  In a  rigorously  regulated accreditation program, in which specific
 and perhaps  severe accreditation criteria have to be met, it  may  take more  than a
 year  for a  device to meet the criteria  and be put on the market.  This would
 assume,  in most  cases, that the device  was ready for mass production  at the time
 the accreditation was begun.  For  example, although accreditation criteria  for
 used  car exhaust control emission  and fuel evaporative loss control devices were
 initiated in California in  1968, only two exhaust control devices for gasoline-
 fueled vehicles had  been accepted  under these criteria as of  this report.   These
 were  accepted in late 1971  and  early  1972.  Special incentives, such  as State-
 financed accreditation programs, could  possibly accelerate and shorten the  time
 required for accreditation  and marketing of a device.

 6.1   VEHICLE APPLICABILITY  OF RETROFIT  DEVICES

 The retrofit study program  was  focused  on the evaluation of those devices designed
 for use on "uncontrolled" vehicles.   These vehicles are considered those which have
 no exhaust or fuel evaporative controls, but  may have crankcase blowby controls.
As shown in Table 6-1, the  uncontrolled vehicle population varies nationally in
 terms of model year  depending on whether a car was sold new in or outside California.
 Exhaust controls were required on new cars sold in California beginning in  1966 and
 on new cars sold nationally  in  1968.  These controls are for  CO and HC only.  NOx
 controls will not be required Federally until 1973,  but were  required on new cars
 in California beginning in  1971.(1)   Crankcase blowby controls have been in effect
 since 1961 in California and since 1963 nationally;  and fuel  evaporative controls
were required in California and nationally in 1970 and 1971,  respectively.

 6.1.1  Pre-1968 Model Vehicles

 Since approximately  10 percent  of  the nation's cars are located in California, it
 is evident that the  retrofit controls for exhaust systems documented  in this study
(l)The 1973 national emission standard for NOx was specified in Federal Register
   Volume 36,  No. 128,  Part II,  dated 2 July 1971.  The California NOx standard
   for 1971 was specified in the California Health and Safety Code, Chapter 4,
   Article 2,  Paragraph 39101.5.
                                        6-1

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Table 6-1.  LIGHT-DUTY VEHICLE POPULATION AND TYPE OF EMISSION CONTROL (1)
ITEM
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
MODEL
YEAR
1970
1969
1968
1967
1966
1965
1964
1963
1962
1961
1960
1959
1958
1957
1956
1955-
AGE
YEARS
1.5
2.5
3.5
4.5
5.5
6.5
7.5
8.5
9.5
10.5
11.5
12.5
13.5
14.5
15.5
16.5+
MILEAGE (1)
13,100
22,500
31,900
41,300
50,700
60,100
69,500
78,900
88,300
97,700
107,100
116,500
125,900
135,300
144,700
154,100+
PERCENT
OF
TOTAL
9
12
11
10
9
9
7
7
6
5
4
3
3
1
1
3
VEHICLE
QUANTITY
(MILLIONS)
8.5
11.0
10.2
9.3
8.5
8.5
6.8
6.8
6.0
4.9
4.3
3.4
3.4
1.7
1.7
3.4
DEGREE OF CONTROL
EXHAUST
|
«












(1) Based on an average of 9,400 miles per year.
j^j Federal control coverage
yff\ California control coverage
1
1
Wx
wk.
W,










BLOW-
BY
1
iS
M
•
i
ii
it









m.
H






EVAPOR-
ATION
2













PERCENT
TOTAL
32



42






26






                                   6-2

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would  be  applicable  to  90  percent  of  the pre-1968  light duty vehicle fleet.  This
would  represent  about 60 percent/of the light duty vehicles in the nation.  Blowby
controls,  however, would be  applicable to  only  90  percent  of the pre-1963 vehicles,
or  less  than  25  percent of the vehicle population.  A  fuel evaporative  loss control
system would  be  applicable to 90 percent of  the pre-1971,vehicles.  Thus, the
exhaust  control  systems and  the fuel  evaporative loss  control systems are the
principal methods  for retrofit to  pre-1968 and  pre-1971 vehicles.

6.1.2  Post-1968 Vehicles

The applicability  of exhaust control  retrofit devices  to vehicles already equipped
with exhaust  controls depends on the  type  of control incorporated in the vehicles
when produced.   The  factory  installed control devices  used on post-1965 vehicles
in  California and  on post-1967 nationally  fall  into  two categories:  engine modifi-
cation and air injection.                                  .

The engine modification systems include many functional changes such as lean carbu-
retion,  ignition timing retard at  idle speed, combustion chamber redesign, and
manifold  redesign.   Several  of the engine  modification systems incorporate one or
more of  the design principles on which the retrofit  devices are based.

The air  injection  system incorporates some, of the  features of.the engine modifica-
tion system.  It includes  an air pump that injects air into the exhaust manifold
to'more  completely oxidize the hydrocarbons  and carbon monoxide.

To  specifically  determine  the applicability  of  each retrofit device or  generic
group  to  these production-controlled  vehicles,  a detailed  study and test program
would  have to be performed.  The functional  characteristics of each original equip-
ment modification  of each  auto manufacturer  would  have to  be compared to the retro-
fit device characteristics and a cost effectiveness determination made.  In general,
it  can be  stated that not  all of the  retrofit devices  would be feasible or practical
for additional emission reduction  of  vehicles already  controlled.  Those retrofit
devices which appear to be reasonably feasible  for retrofit to controlled vehicles .
(1968  through 1971 for  all of U.S. and 1966  through  1971 for California vehicles)
are discussed below.

6.1.2.1   Catalytic Reactors, Thermal  Reactors,  and Exhaust Gas Afterburners

In  most  cases, catalytic reactors, thermal reactors, and exhaust gas afterburners
could  be  retrofitted to 1968-1971 model cars which already have some form of exhaust
control,  to provide  further  control of CO  and HC.  Installation requirements and
costs  would be similar  to  those of the pre-1968 vehicles evaluated in the retrofit
study  program.                          .

The main difference  in cost would be whether the vehicle is already equipped with an
air  injection pump,  or if  it has lean carburetion.   The 1968-1971 model vehicles
which are already equipped with exhaust control  systems generally have lean air fuel
carburetion, which might provide sufficient air.  Some of the newer developments in
catalysts will reportedly  convert HC,  CO,  and NOx when carburetor mixtures are near
stoichiometric.   The catalyst systems  generally, however, need external air injection
into the reactor for maximum effectiveness, as  do the  thermal reactors and after-   '
burners.    Since the  latter,  in addition,  usually require rich air-fuel carburetion to
support the oxidation process,  they would not generally be compatible with vehicles
                                        6-3

-------
 incorporating  lean  carburetion.  Catalytic systems, therefore, would be the most like-
 ly candidate  in  this group  for retrofit  to controlled vehicles.  The cost versus ef-
 fectiveness of this approach would have  to be determined.

 6.1.2.2   Exhaust  Gas Recirculation

 Exhaust  gas recirculation (EGR) systems  recirculate exhaust gases to the induction
 system and dilute the air-fuel mixture delivered by the carburetor, with resultingly
 lower combustion  temperature and inhibition of NOx formation.  These systems can be
 retrofitted to cars already equipped with exhaust controls for CO and HC.  The in-
 stallation requirements and costs would  be quite similar to those evaluated in the
 retrofit program  for pre-1968 cars.  On  cars which are factory equipped with exhaust
 emission control  systems with relatively lean carburetor mixtures, the addition of
 an EGR system  may present some driveability problems if the rate of exhaust gas re-
 circulation is excessive.(1)

 6.1.2.3   Distributor Vacuum Advance Disconnect

 The distributor vacuum advance disconnect system provides a means of lowering HC and
 NOx emissions  at  part throttle operation.  This approach would probably be the most
 cost effective to install on vehicles already equipped with HC and CO exhaust control
 systems.  However,  this system may degrade part-throttle driveability operation and
 fuel consumption.   Wide open throttle performance would not be affected, because in
 this mode of operation there is no manifold vacuum to operate the distributor vacuum
 advance  unit anyway.(1)

 6.1.2.4  Air Bleed  to the Intake Manifold

 Air bleed systems can be retrofitted to vehicles already equipped with HC and CO ex-
 haust control  systems.  However, it is possible that these retrofit devices could
 cause serious  problems by overleaning the carburetor mixture, since the 1968-71 ve-
 hicles equipped with exhaust control systems already have a lean main circuit car-
 buretor mixture.  The air bleed system,  in metering additional air, may cause exces-
 sive leaning.  This is particularly true in part throttle operation (10-18 inches of
 mercury manifold vacuum), because the air-bleed-to-carburetor-mixture flow ratio in
 the manifold may be excessive.  This condition could lead to surging problems during
 cruise mode operations and could also result in lean misfire.  Air bleed systems may
 also increase  NOx slightly because of the increased availability of oxygen in the
 combustion chamber.

As  higher engine  loads are required (less than 10 inches of mercury manifold vacuum),
 the air-bleed-to-carburetor-mixture flow ratio becomes less.  Therefore, the air
 bleed systems  should not affect driveability or engine performance at heavy engine
 loads.

 6.1.2.5   Gaseous Fuel Conversions

Most light duty vehicles could be converted to run on liquefied petroleum gas or
compressed natural gas, if the initial costs were not so high and if the supply of
these fuels was adequate.   Gaseous fuels enable the CO,  HC, and NOx reduction advan-
tages provided by high air-fuel ratios.  In addition, it is generally agreed that the
(1) California recently passed a law requiring NOx control systems on 1966-70 model
    vehicles, as specified in California Air Resources Board Resolution 71-110,
    17 November 1971.
                                         6-4

-------
HC emission byproducts from gaseous fueled vehicles are of lower photochemical smog
reactivity than those from gasoline fueled vehicles; however,  no Federal reactivity
scale has been defined to allow quantitative correction for this factor.

The reduction in recurring vehicle maintenance costs that use  of gaseous fuel sys-
tems has indicated, could offset their high initial costs, possibly within a 50,000-
mile service life.  Since the natural gas and oil industry is  not presently geared
to supply the quantity of fuel that would be needed to support widespread conver-
sions, the application of these conversions appears to be limited to fleet vehicles
through the 1970's.(l)

6.1.2.6  Evaporative Emission Control Systems

Fuel evaporative control systems control the hydrocarbons which would otherwise
evaporate from the fuel tank and carburetor vents of a car. Most of the evaporation
losses come from the carburetor external vents, and controls for this would be rela-
tively difficult to retrofit.  Fuel tank evaporation control systems would be easier
to retrofit than carburetor vents.

Evaporative control system retrofitting may produce some serious safety hazards.   An
example would be a fuel tank evaporation control system installed in the trunk of a
car.  Any leaks could cause excessive fumes, which could enter the passenger com-
partment.  Installation of these systems would require careful design to avoid these
hazards.

No retrofit evaporative control systems were supplied for evaluation in the retrofit
study program.

6.2  RETROFIT DEVICE DEVELOPMENT STATUS AND APPLICABILITY SUMMARY

Table 6-2 summarizes the development, manufacturing, and marketing status of devices
evaluated in the retrofit study, as well as the estimated uncontrolled vehicle
applicability.  The table columns are defined as follows:

     a.  Development Status;  This column defines the development status of the
         device in that it indicates that a prototype (P) was  developed and
         tested on a vehicle, or that the device is in a production (PR) con-
         figuration.  Also of importance is whether or not the developer has
         applied for a patent (DPP) - Patent Pending, or has an existing patent
         (DP) on his device.

     b.  Estimated Applicability to Uncontrolled Used Cars; The percentage of
         the uncontrolled used car population which could be retrofitted with
         the device is represented by this column.  Values are estimated from
         retrofit developer inputs.
(1) "Emission Reduction Using Gaseous Fuels for Vehicular.-Propulsion," Final Report
    on EPA Contract 70-69 by the Institute of Gas Technology,  June 1971.
                                        6-5

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Table 6-2.  DEVELOPMENT STATUS AND APPLICABILITY OF DEVICES
                     EVALUATED IN RETROFIT PROGRAM




DEVICE
NO.





DESCRIPTION




DEVELOPMENT
STATUS'!)
ESTIMATED
APPLICA-
BILITY TO
UNCONTROLLED
USED CARS
00
GROUP 1 EXHAUST EMISSION CONTROL SYSTEMS
Exhaust Gas Control Systems - Type 1.1
62
93
96
292
31
244
463
468
308
425
164
322
Catalytic Converter
Catalytic Converter with Exhaust Gas Recirculation, Spark Modification, and Lean Idle Mixture
Catalytic Converter with Distributor Vacuum Advance Disconnect
Catalytic Converter
Thermal Reactor by Turbine Blower Air Injection
Rich Thermal Reactor
Rich Thermal Reactor with Exhaust Gas Recirculation and Spark Retard
Lean Thermal Reactor with Exhaust Gas Recirculation
Exhaust Gas Afterburner
Exhaust Gas Afterhurner
Exhuast Gas Filter
Exhaust Gas Backpressure Valve
p
p
P/DP
PR/DP
P
P/DP
P
P
P/DP
PR/ DP
P
P
No data
No data
90
90
No data
80
No data
No data
90
90
90
No data
Induction Control Systems - Type 1.2
1
42
57
325
401
418
433
458
462
10
245
'246
294
172
384
430
440
33
56
288
295
317
100
22
Air Bleed to Intake Manifold
Air Bleed to Intake Manifold
Air Bleed with Exhaust Gas Recirculation and Vacuum Advance Disconnect
Air-Vapor Bleed to Intake Manifold
Air-Vapor Bleed to Intake Manifold
Air Bleed to Intake Manifold
Air-Vapor Bleed to Intake Manifold
Air Bleed to Intake Manifold
Air Bleed to Intake and Exhaust Manifolds
Throttle-Controlled Exhaust Gas Recirculation with Vacuum Advance Disconnect
Variable Camshaft Timing
Speed-Controlled Exhaust Gas Recirculation with Vacuum Advance Disconnect
Exhaust Gas Recirculation with Carburetor Modification
Intake Manifold Modification
Air-Fuel Mixture Dlffuser
•Induction Modification
Air-Fuel Mixture Deflection Plate
Carburetor Modification, Main Jet Differential Pressure
Crankcase Blowby and Idle Air Bleed Modification
Carburetor Main Discharge Nozzle Modification
Carburetor with Variable Venturi
Carburetor Modification with Vacuum Advance Disconnect
Turbocharger
Electronic Fuel Injection
PR
PR
P
PR
PR
P
PR
P
P
PR
PR
P
P
P/DP
P
P
p/nr
p
P/DPP
P
PR
P/DPP
P
P
90
90
90
90
90
90
90
No data
No data
90
90
90
No data
90
90
90
90
90
90
90
90
90
No data
No data
Ignition Control Systems - Type 1.3
69
175
23
95
259
268
296
Electronic-Controlled Vacuum Advance Disconnect and Carburetor Lean Idle Modification
Ignition Timing Modification with Lean Idle Adjustment
Electronic Ignition Unit
Ignition Spark Modification
Photocell-Controlled Ignition System
Capacitive Discharge Ignition
Ignition Timing and Spark Modification
P
PR
P
PR/DPP
P
PR
P/DPP
90
90
No data
100
*)0
10
90
Fuel Modification - Type 1.4
52
182
465
36
279
282
457
459
460
461
464
466
LPG conversion
Fuel and Oil Additives
Fuel Additive
Fuel Conditioning by Exposure to Electromagnetic Field
Fuel Conditioner
LP Gas Injection
Water Injection
LPG Conversion with Deceleration Unit
Compressed Natural Gas Dual-Fuel Conversion
LPG Conversion with Exhaust Reactor Pulse Air Injection and Exhaust Gas Recirculation
Methanol Fuel Conversion with Catalytic Converter
LPG-Gasoline Dual-Fuel Conversion
PR/DP
PR
P
P
PR /DPP
PR/DP/DPP
No data
PR/DP
PR
No data
P
PR/DP
No data
No data
No data
No data
100
90
No data
No data
No data
No data
No data
No data
GROUP 2 CRANKCASE EMISSION CONTROL SYSTEMS
24
160
170
315
427
Heavy Duty Positive Crankcase Control Valve with Air Bleed
Closed or Open Blowby Control System with Filter
Closed Blowby Control System
Closed Blowby Control System
Closed or Open Rlowby Control System with Filter
PR
PR
PR/DP
PR /DP
PR
No data
90
90
90
90
GROUP 3 EVAPORATIVE EMISSION CONTROL SYSTEMS
467
Fuel evaporation control system
(2)
No data
GROUP 4 EMISSION CONTROL COMBINATIONS
59
165
408
469
Three-Stage Exhaust Gas Control System
Exhaust Gas Af terburner/Recirculation with Blowby and Fuel Evaporation Recirculation
Exhaust Gas and Blowby Recirculation with Intake Vacuum Control and Turbulent Mixing
Rich Thermal Reactor with Exhaust Gas Recirculation and Particulate Control
P
P
P/DP
P
90
75
90
No data
(1) P » PROTOTYPE . (2) No retrofit device of this type was found to exist except in combination with another
PR - PRODUCTION device (refer to paragraph 4.1.3).
DP - DEVICE PATENTED
DPP - DEVICE PATENT PENDING
                             6-6

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7 - GUIDELINES FOR
 RETROFIT METHODS

-------
                                     SECTION 7

            GUIDELINES FOR SELECTING AND IMPLEMENTING RETROFIT METHODS


The determination that certain retrofit methods are feasible for use in controlling
used car emissions is only the starting point for applying these methods.  Care-
fully planned effort is required on the part of agencies responsible for air quality
to define the requirements for retrofit methods and the standards or criteria they
must meet in their respective regions.  Equally well planned and managed effort is
required to select those devices offering the optimum solution to a region's air
quality control requirements and then to manage the everyday affairs of an opera-
tional retrofit program.

The evaluation methodology developed in the retrofit study is a basic tool that can
be used by air quality control agencies to screen and select optimum retrofit
devices to meet their requirements.  In addition to using this methodology, there
are a number of other steps which have to be planned for and accomplished in imple-
menting a retrofit program.  The basic approach for selecting and implementing a
retrofit method of control may be summarized in the following steps:

     a.   Define the emission reduction that would be required from the used car
          population.

     b.   Define the characteristics of the used vehicle population to which
          retrofit methods would be applicable.

     c.   Identify feasible retrofit methods for application to that vehicle
          population.

     d.   Determine which retrofit methods are most cost effective for the desired
          level of emission control, giving due consideration to facilities
          and labor requirements for implementing the retrofit program.

     e.   Define the retrofit device accreditation program.

     f.   Conduct the cost effectiveness studies required to verify the retrofit
          program approach as being the most appropriate method of emission control.

     g.   Prepare an implementation plan.

     h.   Initiate and maintain the implementation plan.

7.1  DEFINING THE REQUIRED EMISSION REDUCTION

The State implementation plans required by the Clean Air Amendments Act of 1970
should be the means  for identifying used car emission control requirements.   The
air pollution caused by the used car population would have to be sufficiently
                                        7-1

-------
 detrimental to human health or welfare to justify a retrofit  program.   The  control
 of air quality is more complex than mere control  of the  motor vehicle  population,
 but those pollutants predominantly caused by vehicles  can be  identified and the
 impact on human health and welfare assessed.

 7.2  DEFINING THE RETROFIT VEHICLE POPULATION

 The vehicle population to be controlled is a decisive  factor  in the  type of retrofit
 method to be implemented.   The uncontrolled vehicle population has  to  be of suffi-
 cient size and density to justify the  program.  Vehicle  population  surveys  should
 be conducted in air quality control regions where population  densities and  the
 meteorological conditions  of air  basins are known to influence the air pollution
 problems  caused by vehicles.   These surveys should be  designed to establish the
 vehicle population profile in terms of vehicle  model year,  engine displacement,  and
 ownership.   Further,  the survey should establish  the vehicle  owner attitudes  and
 preferences concerning retrofit controls,  their costs, and the means of implementing
 such controls.

 7.3  IDENTIFYING CANDIDATE RETROFIT METHODS

 Retrofit  methods offering  the type and level  of control  required by  the air pollution
 problem of  the  region  under  study  should be identified.  All  candidate  methods should
 be  identified  on the basis of the  following performance  parameters:

      a.   Emission  reduction  effectiveness

      b.   Effect on safety, driveability,  and vehicle  performance including fuel
          consumption  changes

      c.   Reliability  and  maintainability

      d.   Development  status

      e.   Initial and  recurring cost

 Each  parameter  should  be given a quantitative value  that represents the minimum
 criteria  that a  device has  to  meet  in  order to  be  identified  as a candidate for
 use.   These  criteria will  provide  a means  of screening devices  on an initial  basis
 prior  to  indepth evaluation.

 The feasibility  of  a retrofit  control  system can be  determined  by comparing its
 performance  to a set of evaluation  criteria.  Table  1-2  lists  the evaluation
 criteria used in this  study and may be  changed  to  fit  the requirements  of
 the evaluator.   A device would be  considered feasible  if it can meet the evalu-
 ation  criteria.

 7.4  DETERMINING COST  EFFECTIVE RETROFIT METHODS

Each device  identified as a candidate should be evaluated by means of the formal
analytical evaluation methodology developed through  the retrofit study.  This
evaluation methodology provides a systematic means of objectively evaluating alter-
native devices in terms of their relative effectiveness and costs and performance.
 The methodology  can be exercised either by  computer  or by manual means.  A sample
manual exercise  of  the evaluation methodology is shown in Appendix A.
                                         7-2

-------
 7.5  DEFINING THE CERTIFICATION PROGRAM

An essential element in approving a particular device or devices for use in a State
 or region is the accreditation program that demonstrates that the .device actually
 performs in the manner in which it was intended.  If the air quality control agency
 does not have significant statistical confidence in a device then an accreditation
 program of adequate size should be conducted by the developer.  Such elements as
 sample size, reliability, durability, maintainability, and effectiveness should be
 addressed in the design of the accreditation test program.  The accreditation plan
 must include several key elements such as:

     a.   General provisions for retrofit systems

     b.   Emission level standards

     c.   Accreditation procedures

     d.   Test procedures

     e.   Compliance to standards.

 7.6  COST EFFECTIVENESS STUDIES OF ALTERNATIVE PROGRAMS

 The cost effectiveness of a retrofit device program for the uncontrolled vehicle
 population must be evaluated in order to decide whether the retrofit method of con-
 trol is the most effective when all alternative methods are taken into consideration.
Alternative methods for used car control such as periodic vehicle inspection and
maintenance must be weighed against the retrofit approach to determine which is the
most cost effective for a particular region.

 7.7  PREPARING AN IMPLEMENTATION PLAN

A detailed plan is required by which to control the accreditation of feasible
devices for use, to control the installation, and to control the long term mainte-
nance and continuing effectiveness of the installed devices.

An accreditation program for the certification of retrofit emission control systems
for used vehicles must be rigorously planned and managed if the retrofit systems
are to be effective in reducing vehicle air pollution.

The overall implementation plan should specify how and when the selected retrofit
method will be incorporated on the uncontrolled vehicle population, and what means
will be used to ensure long-term maintenance and effectiveness of the device.

7.8  IMPLEMENTING THE PLAN

A formally chartered agency should be assigned the responsibility for implementing
and maintaining the control plan.   This responsibility includes such requirements as:

     a.   Training of retrofit installation, maintenance, and repair personnel.

     b.   Establishment of periodic inspection requirements or surveillance
          techniques.
                                        7-3

-------
     c.   Overall program administration within the air quality control regions
          of concern.

The effective implementation and management of a sound retrofit plan is of paramount
importance, if the calculated reduction in vehicle emissions is to be realized.
This is the enforcement phase of the program,  wherein the several millions of
uncontrolled vehicles are brought under control by the enforcement agency.  As
indicated by the three requirements listed above,  this phase implies controlling
the developers, the vehicle repair personnel,  and  the many vehicle owners.  A task
of such a magnitude requires that the preparation  described in the previous steps
be adequate and sound.

Of further consideration in the establishment  and  implementation of a viable
retrofit program is that the above steps not only  consider the present time and
circumstances, but that all the predictable variations that could occur in the
future years be recognized and accommodated in the program.  A continuing program
should be instituted which provides a periodic evaluation of the air quality problem
and the effectiveness of the program.
                                        7-4

-------
    APPENDIX A - SAMPLE
METHODOLOGY CALCULATIONS

-------
                                    APPENDIX A

               SAMPLE PERFORMANCE EVALUATION METHODOLOGY CALCULATION
A retrofit system was randomly selected to demonstrate the use of the evaluation
methodology developed in the retrofit study.

The data required to exercise the sample calculation are presented in Table A-l.
(The device is not identified for this sample calculation.)  These data are from
Appendix E of Volume III.  For the sample calculation, several references are made
to the equations in Section 3 of Volume III.  The determination of the parameters
for the three indexes (Criteria, Performance, and Cost Effectiveness) is in the
order of natural flow.  For example, the Driveability Index must be calculated to
provide an input to the Criteria Index and is later used in the calculation of the
Performance Index.

1.0  CRITERIA INDEX

The development of the Criteria Index is presented in paragraph 3.1 of Volume III.
The purpose of the Criteria Index is to identify any weak characteristics of a
particular device.  For this sample calculation the assumed evaluation criteria
that a device should meet are listed in Table 1-2 (these values could vary for
different States or agencies according to their particular requirements).

1.1  EMISSION STANDARDS FACTOR

Using the assumed standards of 4.5 gm/mi for HC, 46.7 gm/mi for CO, and 3.0 gm/mi
for NOx, the evaluator compares the retrofit emission values as follows:


                    Assumed         Retrofit Test        Difference Between
                   Standards          Emissions           Stds & Retrofit
                  (gms/mile)          (gm/mile)             (gms/mile)
        HC            4.50               6.17                   -1.67
        CO           46.70              89.83                  -43.13
        NOx           3.00               1.88                    1.12


HC and CO levels are greater than the assumed standards.  This causes the emission
standards factor to receive a rating of "0".  The negative values indicate emission
levels are above standards.
                                        A-l

-------
          Table A-l.  INPUT DATA FOR SAMPLE CALCULATION USING EVALUATION
                                   METHODOLOGY
1.   Emission Data (Gm/Mile):
     Baseline:
     Retrofit:

2.   Safety Factor:

3.   Driveability Test Data:
                                   HC

                                  A. 54
                                  6.17
  CO
70.78
89.83
NOx
2.39
1.88
                                  This device received a safety factor of 1.
                                         Baseline   Retrofit   Retrofit-Baseline
     Test           Parameter            	   	

     Cold   Stall at Idle                   1          0
            Stumble                         2          6
            Stretchiness                    0         10
            Start time, sec                 0.5        0.5
            Attempts                        1          1
     Hot    Stretchiness                    0         12
            Start time, sec                 0.5        0.5
            Attempts                        1          1
            Avg Acceleration Time, sec     17.3       23.9

4.   Installation and Recurring Cost Data:
     Retrofit kit cost = $50.00
     Installation time =2.25 hours
     Labor rate        = $12.50/hour
                                                               0-1 = -1
                                                               6-2 = 4
                                                               10-0 = 10
                                                               0.5(1)-0.5(1) = 0
                                                               12-0 = 12
                                                               0.5(1)-0.5(1) = 0
                                                               23.9-17.3 = 6.6
     MTTR  = 0 hrs (1)
     MMBPF = 75,000 miles (1)
     MMBTF = 75,000 miles (1)
     MTTM  = 0.50 hrs
     MMBM  = 25,000 miles
                                         Lc  = $12.50/hour
                                         CRP = 0 (1)
                                         CMP = 0 (2)
                                         aD  - 0.0661 gal/mile
                                         (rB  = 0.0594 gal/mile
                                         G,  = $0.35
     NOTES: (1) For this device the engineering evaluation showed that the mean
                miles before partial failure (MMBPF) and the mean miles before
                total failure (MMBTF) are both 75,000 miles.  Therefore, no labor
                (MTTR) and repair parts cost (C  ) are required.
                                               RP
            (2) No maintenance parts required for scheduled maintenance.

5.   Reliability Data:

     Mean-miles-before-total-failure (MMBTF) = 75,000 miles.

6.   Maintainability:

     Mean-miles-before-maintenance (MMBM) = 25,000
                                        A-2

-------
1.2  EMISSION BASELINE FACTOR

The emission baseline factor prevents HC, CO, and NOx pollutant level increase from
baseline levels with the device installed.  An experimental error is allowed due to
variations in test repeatability  (10 percent used in this study) before the emission
baseline factor is set equal to zero.  The per unit reductions for the three pollu-
tants are obtained using Eqs.  (3.3), (3.4) and (3.5) from Section 3, Volume III and
the data from Table A-l:
     HC Reduction,  (R)
     CO Reduction, (R)
                      HC
                      CO
                              LBHC "EDHC
                                 BHC
                              JBCO
       "EDCO
                                 JBCO
                 4.54 -6.17
                    4.54
70.78 -89.83
    70.78
               -0.36 per unit
                 (A.I)
                               =  -0.27 per unit   (A.2)
   NOx Reduction, (R)
                     NOx
  EBNOx "EDNOx

     EBNOx
  2.39 -1.88
     2.39
0.21 per unit    (A.3)
The negative values indicate an emission increase above baseline levels.  HC and CO
increased by more than 0.10 (10 percent).  Therefore, the emission baseline factor
is zero.
1.3  SAFETY FACTOR

The safety factor was determined by an engineering evaluation of the device.  Any
potential dangers were identifed with respect to design, installation, or modes of
operation.  This device received a safety factor of 1 (Table A-l).

1.4  CRITICAL DRIVEABILITY FACTOR

In the Driveability Index (DI), the sum of the "without device" driving problems is
subtracted from the sum of the "with device" driving problems to arrive at a drive-
ability variation AD, for each parameter:
     A.D  =  D
             with device
-  D
    without device
There are five driveability test parameters that are considered to be critical.
These critical driveability parameters, if they exist, have an adverse effect on
the safety and, therefore, the acceptability of the device being evaluated.  These
critical driveability parameters are:
               Parameter

       a.  Stall on acceleration
       b.  Backfire
       c.  Stall at idle
       d.  Stall on acceleration
       e.  Backfire
                      Test                  AD

            Cold Start driveaway test        0
            Cold Start driveaway test        0
            Hot Start driveaway test         0
            Hot Start driveaway test         0
            Hot Start driveaway test         0
                                        A-3

-------
Since there were no critical driveability changes for this device, the critical

driveability factor is one.



1.5  GENERAL DRIVEABILITY FACTOR



The criterion for the general driveability factor requires that the Driveability

Index be no greater than 1.0.  Therefore, it is necessary to calculate the Drive-

ability Index at this point.  As defined in Eq. (3.7), Section 3, Volume III, the

Driveability Index equation is:




                        T,T        nm-r        ,-,™,        R    5   D





                                                       'STM + "lO ADH



                  AD_ .  -, „ ^n .  -, „ ,,-„„ , ,  .  ,  , -14 ^^TN . cold
D + ai2 ADs + ai3 ADsu)hot + (ai4 ADTN)




   )hot + "
                 5 ADTNhot    16   A     ai+az... +a16



     Where:  S.  =  1/3 (Scaling factor)



The nine parameters measured during the cold driveability test and the hot drive-

ability test were:



     AD     =  Rough Idle (Cold start and hot start test)
       K..L


     ADorm.  =  Stumble (Cold start and hot start test)
       STM


     AD     =  Hesitation (Cold start and hot start test)
       H


     AD     =  Detonation (Cold start and hot start test)



     AD     =  Stretchiness (Cold start and hot start test)
       O


     AD     =  Surge (Cold start and hot start test)
       b U


     AD     =  Average cranking time (T) times number of engine start attempts (N)

               (Cold start and hot start test)



     AD     =  Stall at Idle (Cold test only)
       b 1 i.


     AD.     =  Acceleration from 0-60 mph, in seconds (Hot start only)
                                        A-4

-------
Additionally, the weighting coefficients (a.) used in this study were:
Cold Driveability


CU
1-1
T3
H

JC
60
3
O
f*
ol
0.3333



-------
1.6  INSTALLATION COST FACTOR
The installation cost includes retail cost of  the device,  labor  cost  to  install  it,
and any special adaptive parts that may be needed.  From Table A-l, the  installation
cost is:
      (Retrofit kit cost) plus  (installation cost)

      $50.00 + 2.25 hrs  ($12.50/hr)  =   $78.13
                                                                (A. 6)
With an installation cost of less than the $85.00 criterion,  the  installation cost
factor is equal to one.

1.7  THE RECURRING COST FACTOR

The recurring cost of the device takes into account all  of  those  incremental  costs
due to the continued operation of the retrofit device.   It  includes  the  cost  of
periodic maintenance of the device, repairs for  failed parts,  total  replacement  if
required, and any incremental losses in fuel economy.  The  recurring cost  is  given
by the equation:
      Recur

Where:

     MTTR

     MMBPF

     MTTM

     MMBM


     Lc

     CRP

     SlP
             _ /MTTR    MTTM\        CRP    SlP      (        .
               \ TurMmjf   TWO/TDM / -"/I    •UVTDTCC'   VtX/TDVt     \ °T» ~ ® T>'
V MMBPF
              /  C
MMBPF   MMBM
                                                                (A. 7)
Mean-time-to-repair, hours

Mean-miles-before-partial-failure, miles

Mean-time-to-maintain, hours

Mean-miles-before-maintenance, miles

Labor rate, dollars per hour

Average cost of repairs, dollars per repair

Average cost of maintenance parts, dollars per maintenance action

Fuel consumed with device installed, gallons per mile

Fuel consumed without device  installed  (baseline),  gallons per  mile

Fuel cost, dollars/gallon
                                        A-6

-------
 Substituting  the  values from Table A-l into Eq.  (A.7):

                                                      0
      C
= /   °   ,   0.50 \/hours\ /$12.50\
  \75,000   25,000/lmile / \ hour /
      'Recur    \ 75, 000   25,000/Vmile  / \ hour  /     75,000    25,000  \miles/


                 + (0.0661  -  0.0594) Hr          =   $°-00259/mile            (A-8>
 The  assumed  recurring  cost  criterion  is  $0.00125/per mile  and  the  limit  is  exceeded.
 Therefore, the  recurring  cost  factor  is  zero.

 1.8  RELIABILITY FACTOR

 From Table A-l, the MMBTF is 75,000 miles, which meets the minimum reliability
 criterion.   The reliability factor is  one.

 1.9  MAINTAINABILITY FACTOR

 The  MMBM  given  in Table A-l is 25,000  miles and is greater than the minimum maintain-
 ability criterion of 12,000 miles.  Therefore, the maintainability factor is one.

 1.10 AVAILABILITY FACTOR

 The  availability factor reflects the inconvenience to the car  owner and  is  the ratio
 of the total miles of  service life before device failure to the total hours for
 failure repair and periodic maintenance  of the device.  The value for the avail-
 ability factor is given by  the following equation:

                                 MMBPF
     Availability, A   =  - .      . -  Miles per Repair and
                                         (MT™)  ""ntenance Hour               (A.9)

Where:

     MMBPF  =  Mean-miles-before-partial-failure

     MMBM   =  Mean-miles-before-maintenance

     MTTR   =  Mean- time-to-repair, hours

     MTTM   =  Mean-time-to-maintain, hours

Substituting values:


     A  =  -  * nn_ -  =  50,000 miles/repair and maintenance
                           (0.5)     hour                                    (A. 10)
This far exceeds the minimum criterion of 12,000 miles per repair hour so the
availability factor is equal to one.
                                        A-7

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 1.11   CRITERIA INDEX ANALYSIS

 A summary of the Criteria  Index Factor  is  as  follows:
                                         Criterion       Does  the Device  Pass
                                         Factor       the Evaluation Criteria?
     a.   Emission  standards  factor            0                  No

     b.   Emission  baseline factor             0                  No

     c.   Safety  factor                        1                  Yes

     d.   Critical  driveability  factor         1                  Yes

     e.   General driveability factor          1                  Yes

     f.   Installation cost factor             1                  Yes

     g.   Recurring cost factor                0                  No

     h.   Reliability factor                   1                  Yes

     i.   Maintainability factor               1                  Yes

     j.   Availability factor                  1                  Yes

The  Criteria Index results show that the device does not meet the emission standards,
emission baseline, and recurring cost factors.  This presents a warning to the
evaluator selecting a particular retrofit device to give these factors closer
attention.  At this point the evaluator may  exclude a particular device from further
evaluation as a retrofit emission control system.

The  reader is cautioned to note that the device used for this example was randomly
selected and installed on one test vehicle.  Several tests should be conducted on
each device being evaluated to establish mean values and statistical validity.  The
results  shown here are not conclusive.

2.0  PERFORMANCE  INDEX

The Performance Index (PI) is represented by a summation equation designed to obtain
a quantitative rating of the devices under evaluation.   This equation measures the
relative performance ratings of the device, and allows  an objective evaluation even
if it does not pass State or regional evaluation criteria index requirements.

The general form of the Performance Index (PI) is given by the following equation:

                               (Emission  \       /Drive- \        /
                               Index, Per\   _ c  / ability\   .  c  /    Cost
                               Unit  of    I      M Index   I      Jl    Index
                               Reduction /	\Points /	\$/100 miles/
  Performance Index, PI =                       C  +  C  + C                      (A.11)
                                        A-8

-------
For this example, the weighting coefficients C]_, C2, and Cy are 4, 1, and 2, as
defined in paragraph 3.4  of Volume III.

2.1  EMISSION INDEX

The emission index (El) provides the per unit reduction of vehicle emission reduction
with the retrofit device  installed from the baseline emission level of the vehicle
without the device installed.  For each pollutant, this per unit reduction is
expressed by the following equation:


     _T     	±	  .     , EBHC"EDHC\ . ••   /EBCO"EDCOl
     *"  =  _          : ~	  I QTT^ I   p	1' Pf,  I   p	
                                      BHC   /    0 \   BCO
Where "S^" is a scale factor.  It is "1" for the emission term.

Equal weighting is assumed for the emission weighting coefficients.  Therefore,



Substituting the baseline and retrofit emission levels values given in Table A-l:

                     /4.54 - 6.17\
                                         (70.78 - 89.83\        (2.39 - 1.88\]
                                         y    70-78    j +  a)  \    2>39   ;j
     El  =


         =  -0.139                                                            (A.13)

2.2  DRIVEABILITY TERM

The driveability term (DI) was calculated in determining the general driveability
factor of the criteria index and the result was 0.895  See Eq.  (A.5).

2.3  COST INDEX

The Cost Index (CI) combines those parameters which determine the initial costs of
a device and the recurring costs.  The Initial Cost (CDj) is amortized over the
expected life (in miles) of the device.


             *      dollars per mile                                           (A

Where (L-  =  initial cost for parts and installation and MMBTF  =  mean-miles-
before-total-failure.
                                        A-9

-------
The Cost Index  (CI) is:
                T5iT? + CRecurr     d°llarS ^ 10° miles
Where S-  =  Scaling factor  =  100

Substituting the values given in Table A-2 and from Eqs.  (A. 6) and (A. 8):


     CI  =  IQO [   $78.13    + $0,00251  =  $0.364/100 miles                (A.15)
                | 75,000 miles     mile   J

2.4  PERFORMANCE INDEX CALCULATION

Substituting equation results Eq. (A. 13) for the El, Eq.  (A. 5) for the DI, and
Eq.  (A.15) for the CI into Eq. (A. 11) we obtain:


     PI  =  44^+2 [4(-°-139) - 1(0-895) - 2(0.364)]   =  -0.312                 (A. 16)

In general, the negative sign indicates that the cost and/or driveability penalties
are greater than any emission benefits.  In this example, the emission index  increase
was also a penalty.

3.0  COST EFFECTIVENESS INDEX

The Cost' Effectiveness Index (CEI) is obtained by dividing the Emission Index by
the Cost Index.  Using the results of Eqs. (A. 13) and (A.15):


     PFT  _  EI_  _  -0.139  _          Unit Reduction                         ,    .
     CEI  -  Cf  ~  ^364  ~  -°'382   $/100 Miles                           (A'17)

Negative El means increased emission levels above baseline as a result of device
installation.  For this example,  the CEI indicates that money was spent to increase
emissions, a clearly unfavorable situation.
                                       A-10

-------
APPENDIX B - RETROFIT
   DESCRIPTION INDEX

-------
                          APPENDIX B

              RETROFIT SYSTEM DESCRIPTION INDEX
NOTE:  This appendix correlates the retrofit devices evaluated
       with the respective Volume II paragraphs in which the
       devices are described.
                             B-l

-------
RETROFIT SYSTEM DESCRIPTION INDEX
DEVICE
NO.
1
10
22
23
24
31
33
36
42
52
56
57
59
62
69
93
95
96
100
160
164
165
VOL. II
PARA.
4.1.1
4.2.1
4.6.1
5.2.1
7.1.1
3.2.4
4.4.1
6.3.1
4.1.2
6.1.1
4.4.2
4.1.3
9.1
3.1.3
5.1.1
3.1.4
5.2.2
3.1.1
4.5.1
7.2.1
3.4.1
9.2
PAGE
4-3
4-50
4-141
5-22
7-3
3-64
4-104
6-76
4-14
6-5
4-112
4-22
9-1
3-26
5-3
3-29
5-23
3-3
4-139
7-21
3-89
9-5
DEVICE
NO.
170
172
175
182
244
245
246
259
268
279
282
288
292
294
295
296
308
315
317
322
325
384
VOL. II
PARA.
7.1.2
4.3.1
5.1.2
6.2.1
3.2.1
4.2.2
4.2.3
5.2.3
5.2.4
6.3.2
6.2.3
4.4.3
3.1.2
4.2.4
4.4.4
5.2.5
3.3.1
7.1.3
4.4.5
3.5.1
4.1.4
4.3.4
PAGE
7-7
4-80
5-12
6-61
3-31
4-58
4-67
5-25
5-32
6-78
6-67
4-117
3-19
4-79
4-123
5-36
3-73
7-15
4-132
3-95
4-30
4-97
DEVICE
NO.
401
408
418
425
427
430
433
440
457
458
459
460
461
462
463
464
465
466
467
468
469

VOL. II
PARA.
4.1.5
9.3
4.1.6
3.3.2
7.2.2
4.3.2
4.1.4
4.3.3
6.2.4
4.1.7
6.1.3
6.1.6
6.1.4
4.1.8
3.2.2
6.1.5
6.2.2
6.1.2
8.1
3.2.3
9.4

PAGE
4-39
9-15
4-43
3-79
7-27
4-86
4-30
4-91
6-73
4-45
6-35
6-47
6-40
4-46
3-51
6-43
6-66
6-31
8-3
3-58
9-21

                B-3

-------
     APPENDIX C
VOL. II-VI CONTENTS

-------
                     APPENDIX C
                 TABLES OF CONTENTS
                        FOR
          VOLUMES II, III, IV,  V,  AND VI
The tables of contents from Volumes II,  III,  IV,  V,  and
VI are presented in this appendix to provide  an overview
of the subject matter of this report and to aid the
reader in locating subjects of interest.
Volume                                            Page
  II      System Descriptions                      C-3
 HI      Performance Analysis                    C-21
  IV      Test and Analytical Procedures          C-25
   V      Appendices                              C-21
  VI      Addendum for Durability Tests           C-29
                        C-l

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                                   VOLUME  II

                                     CONTENTS


Section    .                                                                  Page

            FOREWORD	„	     iii

            PREFACE	  .  .  .	o  .  .       v

            ACKNOWLEDGMENTS	  .  .  .  .  .     vii

            GLOSSARY	,	    viii

   1        INTRODUCTION .................  	     1-1

            1.1       Definition of Retrofit Method  and Light Duty
                        Vehicle	'................     1-1
            1.2       Retrofit Method Classification System  .......     1-2
            1.3       Data Search and Development  Requirements  ...  ...     1-3
            1.4       System Description  Approach   	     1-4
            1.5       Data Survey Results  	  ...........     1-6

   2        RETROFIT EMISSION CONTROL TECHNOLOGY .............     2-1

            2.1       Pollutants Attributable  to Gasoline-  and  Gaseous-
                        Fueled Vehicles  ...„	<...<,     2-1
            2.2       Vehicle Sources of  HC, CO  and  NOx   .........     2-1
            2.3       Principles of Retrofit Methods for  Controlling
                        Vehicle Emissions  	     2-2
            2.3.1     Exhaust Emission  Control Systems -  Group  1  	     2-2
            2.3.2     Crankcase Emission  Control Systems  -  Group  2  ....     2-9
            2.3.3     Evaporative Emission Control Systems  -  Group  3  ...    2-10

   3        GROUP 1 RETROFIT METHOD DESCRIPTIONS:   TYPE  1.1 - EXHAUST
            GAS CONTROL SYSTEMS	     3-1

            3.1       Catalytic Converters - Retrofit Subtype 1.1.1  ...     3-3
            3.1.1     Device 96: Catalytic Converter with Distributor
                        Vacuum Advance  Disconnect   ....  	  .     3-3
            3.1.2     Device 292: Catalytic Converter ..........    3-19
            3.1.3     Device 62: Catalytic Converter ...........    3-26
            3.1.4     Device 93: Catalytic Converter with Exhaust Gas
                        Recirculation,  Spark Modification,  and  Lean
                        Idle Mixture	  .    3-29
            3.2       Thermal Reactor - Retrofit Subtype  1.1.2  ......    3-31
            3.2.1     Device 244: Rich  Thermal Reactor	    3-31
            3.2.2     Device 463: Rich  Thermal Reactor with Exhaust Gas
                        Recirculation and Spark  Retard ....  	    3-51
            3.2.3     Device 468: Lean  Thermal Reactor with Exhaust Gas
                        Recirculation  .„	„	    3-58
            3.2.4     Device 31: Thermal  Reaction  by Turbine  Blower Air
                        Injection  	  .....    3-64
            3.3       Exhaust Gas Afterburner  -  Retrofit  Subtype  1.1.3  .  .    3-73
            3.3.1     Device 308: Exhaust Gas  Afterburner	„    3-73
            3.3.2     Device 425: Exhaust Gas  Afterburner	    3-79
                                        C-3

-------
Section
                                   VOLUME  II
                               CONTENTS  (CONTINUED)
            3.4       Exhaust Gas  Filter  -  Retrofit  Subtype  1.1.4   ....     3-89
            3.4.1     Device 164:  Exhaust Gas  Filter	     3-89
            3.5       Exhaust Gas  Backpressure Control  -  Retrofit  Sub-
                        type 1.1.5	     3-95
            3.5.1     Device 322:  Exhaust Gas  Backpressure Valve  .....     3-95

            GROUP 1  RETROFIT METHOD DESCRIPTIONS:  TYPE 1.2  -  INDUCTION
            CONTROL SYSTEMS	.  .     4-1

            4.1       Air Bleed to Intake Manifold - Retrofit  Subtype
                        1.2.1	     4-3
            4.1.1     Device 1:  Air Bleed to  Intake  Manifold	     4-3
            4.1.2     Device 42; Air Bleed  to  Intake Manifold	     4-14
            4.1.3     Device 57: Air Bleed  with Exhaust Gas  Recircula-
                        tion and Vacuum Advance Disconnect  	     4-22
            4.1.4     Device 325/433:  Air Vapor Bleed to  Intake
                        Manifold	     4-30
            4.1.5     Device 401:  Air-Vapor Bleed to Intake  Manifold  .  .  .     4-39
            4.1.6     Device 418:  Air Bleed to Intake Manifold	     4-43
            4.1.7     Device 458:  Air Bleed to Intake Manifold	     4-45
            4.1.8.     Device 462:  Air Bleed to Intake and Exhaust
                        Manifolds	     4-46
            4.2       Exhaust Gas  Recirculation - Retrofit Subtype 1.2.2  .     4-49
            4.2.1     Device 10; Throttle-Controlled Exhaust Gas Recir-
                        culation with Vacuum Advance Disconnect   	     4-50
            4.2.2     Device 245:  Variable  Camshaft  Timing  	     4-58
            4.2.3     Device 246:  Speed-Controlled Exhaust Gas Recircu-
                        lation with Vacuum  Advance Disconnect   	     4-67
            4.2.4     Device 294:  Exhaust Gas  Recirculation  with
                        Carburetor Modification  	     4-79
            4.3        Intake Manifold Modification -  Retrofit  Sub-
                        type 1.2.3	    4-80
            4.3.1     Device 172:  Intake  Manifold Modification 	     4-80
            4.3.2     Device 430:  Induction Modification  	     4-86
            4.3.3     Device 440:  Intake  Deflection  Plate  	     4-91
            4.3.4     Device 384:  Air-Fuel  Mixture Diffuser   	     4-97
            4.4       Carburetor Modification  - Retrofit  Subtype 1.2.4  .  .   4-103
            4.4.1     Device 33: Carburetor Modification, Main Jet
                        Differential Pressure   	   4-104
            4.4.2     Device 56: Crankcase  Blowby and Idle Air Bleed
                        Modification 	   4-112
            4.4.3     Device 288:  Carburetor Main Discharge  Nozzle
                        Modification 	   4-117
            4.4.4     Device 295:  Variable  Venturi Carburetor   	   4-123
            4.4.5     Device 317:  Carburetor Modification with Vacuum
                        Advance Disconnect  	   4-132
            4.5       Turbocharged Engine - Retrofit Subtype 1.2.5 ....   4-139
            4.5.1     Device 100;  Turbocharger	   4-139
            4.6       Fuel Injection -  Retrofit Subtype 1.2.6   	   4-141
            4.6.1     Device 22; Electronic Fuel Injection	   4-141
                                        C-4

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Section
                                   VOLUME II

                              CONTENTS (CONTINUED)
            GROUP 1 RETROFIT METHOD DESCRIPTIONS:   TYPE  1.3  -
            IGNITION CONTROL SYSTEMS 	     5-1

            5.1       Ignition Timing Modification -  Retrofit  Subtype
                        1.3.1	     5-3
            5.1.1     Device 69:  Electronic-Controlled Vacuum  Advance
                        Disconnect and Carburetor  Lean Idle  Modification  .     5-3
            5.1.2     Device 175:  Ignition Timing  Modification with
                        Lean Idle Adjustment	    5-12
            5.2       Ignition Spark Modification  - Retrofit Subtype
                        1.3.2	    5-21
            5.2.1     Device 23:  Electronic Ignition  Unit	    5-22
            5.2.2     Device 95:  Ignition Spark Modification 	    5-23
            5.2.3     Device 259:  Photocell-Controlled Ignition System .  .    5-25
            5.2.4     Device 268:  Capacitive Discharge Ignition  	    5-32
            5.2.5     Device 296:  Ignition Timing  and Spark  Modification  .    5-36

            GROUP 1 RETROFIT METHOD DESCRIPTIONS:   TYPE  1.4  -
            FUEL MODIFICATION	     6-1

            6.1       Gas Conversion - Retrofit Subtype  1.4.1   	     6-1
            6.1.1     Device 52:  LPG Conversion	     6-5
            6.1.2     Device 466:  LPG-Gasoline Dual-Fuel Conversion   .  .  .    6-31
            6.1.3     Device 459:  LPG Conversion with Deceleration Unit.  .    6-35
            6.1.4     Device 461:  LPG Conversion with Exhaust  Reactor
                        Pulse Air Injection and Exhaust  Gas  Recirculation.    6-40
            6.1.5     Device 464:  Methanol Fuel Conversion with Catalytic
                        Converter	    6-43
            6.1.6     Device 460:  Compressed Natural  Gas Dual-Fuel
                        Conversion	    6-47
            6.2       Fuel Additive - Retrofit Subtype 1.4.2 	    6-61
            6.2.1     Device 182:  Fuel and Oil Additives	    6-61
            6.2.2     Device 465:  Fuel Additive	    6-66
            6.2.3     Device 282:  LP Gas  Injector	    6-67
            6.2.4     Device 457:  Water Injection   	    6-73
            6.3       Fuel Conditioner -  Retrofit  Subtype  1.4.3  	    6-76
            6.3.1     Device 36:  Fuel Conditioning by Exposure to
                        Electromagnetic Field  ..... 	  .  .    6-76
            6.3.2     Device 279:  Fuel Activator	    6-78

            GROUP 2 RETROFIT METHOD DESCRIPTIONS CRANKCASE EMISSION
            CONTROL SYSTEMS	     7-1

            7.1       Closed System - Retrofit Type 2.1	     7-3
            7.1.1     Device 24:  Heavy Duty Positive  Crankcase
                        Control Valve with Air Bleed	     7-3
            7.1.2     Device 170:  Closed  Blowby Control  System 	     7-7
            7.1.3     Device 315:  Closed  Blowby Control  System 	    7-15
                                     .  C-5

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Section
                                   VOLUME II

                              CONTENTS (CONTINUED)
            7.2        Open Systems  -  Retrofit  Type  2.2	     7-21
            7.2.1     Device 160: Closed  or  Open Blowby Control  System .  .     7-21
            7.2.2     Device 427: Closed  or  Open Blowby Control  System
                        with Filter	     7-27

            GROUP 3  RETROFIT METHOD DESCRIPTIONS EVAPORATIVE  EMISSION
            CONTROL  SYSTEMS  	      8-1

            8.1        Device 467 Absorption-Regenerative Fuel
                        Evaporation Control  System    	      8-3
            8.1.1     Typical Installation Description  	      8-3
            8.1.2     Typical Installation Initial  and  Recurring Cost  .  .      8-3
            8.1.3     Feasibility Summary 	      8-3

            GROUP 4  RETROFIT METHOD DESCRIPTIONS EMISSION CONTROL
            COMBINATIONS 	      9-1

            9.1        Device 59: Three-Stage Exhaust  Gas Control System  .      9-1
            9.1.1     Physical  Description	      9-2
            9.1.2     Functional Description 	      9-2
            9.1.3     Performance Characteristics   	      9-2
            9.1.4     Reliability	      9-2
            9.1.5     Maintainability	      9-2
            9.1.6     Driveability  and  Safety	      9-2
            9.1.7     Installation  Description  	      9-3
            9.1.8     Initial and Recurring Costs   	      9-3
            9.1.9     Feasibility Summary 	      9-3
            9.2        Device 165: Exhaust Gas Afterburner/Recirculation
                        with Blowby and Fuel Evaporation Recirculation .  .      9-5
            9.2.1     Physical  Description 	      9-5
            9.2.2      Functional Description 	      9-6
            9.2.3      Performance Characteristics   	      9-7
            9.2.4      Reliability	      9-8
            9.2.5     Maintainability	      9-9
            9.2.6      Driveability  and  Safety	      9-9
            9.2.7      Installation  Description  	      9-9
            9.2.8      Initial and Recurring Costs   	    9-10
            9.2.9      Feasibility Summary  	    9-10
            9.3        Device 408: Exhaust  Gas and Blowby  Recirculation
                        with  Intake Vacuum Control  and Turbulent Mixing   .    9-15
            9.3.1     Physical  Description 	    9-15
            9.3.2     Functional Description 	    9-15
            9.3.3     Performance Characteristics   	    9-17
            9.3.4     Reliability	    9-17
            9.3.5     Maintainability	    9-17
            9.3.6     Driveability and Safety	    9-17
            9.3.7      Installation Description  	    9-17
            9.3.8      Initial and Recurring Costs   	    9-18
            9.3.9     Feasibility Summary  	    9-18
                                       C-6

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                                    VOLUME  II

                               CONTENTS (CONTINUED)

Section                                                                       Page

            9.4       Device 469:  Thermal Reactor with Exhaust Gas  Recir-
                        culation and Particulate Control 	     9-21
            9.4.1     Physical Description 	     9-21
            9.4.2     Functional Description 	 	     9-21
            9.4.3     Performance Characteristics  	     9-23
            9.4.4     Reliability	     9-24
            9.4.5     Maintainability	     9-25
            9.4.6     Driveability and Safety	     9-25
            9.4.7     Installation Description 	     9-25
            9.4.8     Initial and Recurring Costs  	     9-26
            9.4.9     Feasibility Summary	     9-26

  10        REFERENCES	     10-1

  11        RETROFIT DEVICE INDEX  . .	     11-1
                                    ILLUSTRATIONS

Figure                                                                        Page

 2-1        Effects of Air-Fuel Ratio (Reference 114)   	      2-5
 3-1        Device 96 Catalytic Converter Configuration Tested in
              Retrofit Program - Development Model 	      3-4
 3-2        Device 96 Catalytic Converter with Vacuum  Advance Disconnect
              Installation 	      3-5
 3-3        Device 96 Catalytic Converter with Vacuum  Advance Disconnect
              Functional Diagram 	      3-7
 3-4        Typical Device 292 Configuration for LPG-Fuel Material
              Handling Vehicle (Reference 12)  	     3-19
 3-5        Device 292 Configuration for Gasoline Engine (Reference 12).  .     3-19
 3-6        Device 292 LPG Configuration Catalytic Converter Functional
              Diagram (Reference 12)	     3-20
 3-7        Device 292 Catalytic Converter Light Duty  Vehicle Develop-
              mental Configuration (Reference 12)  	     3-24
 3-8        Device 62 Catalytic Converter Emission Reduction Performance
              Versus Catalyst Temperature (Reference 8)  	     3-27
 3-9        Device 244 Type V Thermal Reactor Physical Configuration
              (Reference 72)	     3-32
 3-10       Device 244 Exhaust Gas Flow Through Rich Thermal Reactor
              (Reference 71)	     3-34
 3-11       Device 244 Rich Thermal Reactor and Intake Manifold Heat
              Interface (Reference 71) 	     3-36
 3-12       Device 244 Rich Thermal Reactor Exhaust Port Insert
              Alternative Configurations (Reference 71)  	     3-38
 3-13       Device 244 Rich Thermal Reactor Emission Reduction Charac-
              teristics Compared to Standard Air Injection (Reference 71).     3-39
                                        C-7

-------
                                    VOLUME II

                            ILLUSTRATIONS (CONTINUED)
Figure
 3-14       Device 244 Rich Thermal Reactor Temperature Profile for
              One 7-Mode Cycle (Reference 71)   	     3-39
 3-15       Effect of Fuel Variables on Average Thickness Losses of  OR-1
              Alloy During Continuous Thermal  Cycling (Reference 2)   ...     3-41
 3-16 .      Device 244 Rich Thermal Reactor Core Equilibrium Tempera-
              tures for Vehicle Operating Modes (Reference 71)  	     3-42
 3-17       Condition of Device 244 Rich Thermal Reactor Components
              After One Hour of Light-Off (Reference 71)	     3-43
 3-18       Device 244 Thermal Reactor Installation (Reference  72)  ....     3-47
 3-19       Device 463 Rich Thermal Reactor Model II Configuration
              (Reference 101)	     3-51
 3-20       Effect of Flame Holders on Device  463 Rich Thermal  Reactor
              Warmup Time During 1968 Federal  Test Procedure (Refer-
              ence 101)	     3-53
 3-21       Device 463 Rich Thermal Reactor Installation on 1971 Ford
              LTD 351-CID Engine (Reference 101) 	     3-56
 3-22       Device 31 Turbine Blower Configuration (Developer Photo) .  .  .     3-64
 3-23       Device 31 Air Injection System Configuration (Developer
              Sketch)	     3-65
 3-24       Device 31 Turbine Blower Air Pumping Characteristics
              (Developer Data) 	     3-66
 3-25       Device 31 Turbine Blower Output as Percent of Engine Inlet
              Airflow (Developer Data) 	     3-66
 3-26       Device 31 Turbine Blower Emission  Test Comparison with
              Conventional Air Pump System (Developer Data)  	     3-68
 3-27       Device 31 Turbine Blower Air Injection System Installation
              (Developer Photo)  .  .	     3-71
 3-28       Device 308 Exhaust Gas  Afterburner Showing Spark Plug (Right
              Side) and Diametrically Opposed  Electrode (Left Side)   .  .  .     3-74
 3-29       Device 425 Exhaust Gas  Afterburner (U.S. Patent No.
              3,601,982)	     3-80
 3-30       Device 164 Exhaust Gas  Filter Components (Developer
              Photograph)	     3-89
 3-31       Device 164 Exhaust Gas  Filter Functional Schematic  	     3-90
 4-1        Device 1 Air Bleed Components	      4-4
 4-2        Device 1 - Functional Schematic Diagram	      4-5
 4-3        Device 1 Air Bleed to Intake Manifold Typical Installation
              (Developer Sketch) 	     4-12
 4-4        Device 42:  Air Bleed to Intake Manifold	     4-14
 4-5        Device 42 Air Bleed to  Intake Manifold Functional Schematic
              (Developer Diagram)  . 	     4-15
 4-6        Device 42 Air Bleed to  Intake Manifold:  Typical Installation
              of Air Valve on Carburetor Air Cleaner (Developer Photo)  .  .     4-19
 4-7        Device 57 Air Bleed with EGR and Vacuum Advance Disconnect
              System Components  .... 	     4-22
 4-8        Device 57 Air Bleed with EGR and Vacuum Advance Disconnect
              Installed on V-8 Intake Manifold (Developer Photo) 	     4-26
 4-9        Device 325/433 Air-Vapor Bleed to  Intake Manifold System
              Components	     4-31
                                        C-8

-------
                                    VOLUME II
                             ILLUSTRATIONS (CONTINUED)

Figure                                                                        Page

 4-10       Device 325/433 Air Injection Needles 	     4-31
 4-11       Device 325/433 Air-Vapor Bleed to Intake Manifold Func-
              tional Schematic (Developer Diagram)  	     4-32
 4-12       Device 325/433 Air Needle System Compared to Standard Needle
              (Developer Diagram)  	     4-33
 4-13       Device 401 Air-Vapor Bleed to Intake Manifold System
              Configuration (Developer Diagram)  	  ....     4-39
 4-14       Device 462 Air Bleed to Intake and Exhaust Manifolds Func-
              tional and Installation Schematics (Reference 90)   	     4-47
 4-15       Device 10 Throttle-Controlled EGR with  Vacuum Advance
              Disconnect System Configuration  	     4-51
 4-16       Device 245 Variable Camshaft Timing Gear	     4-58
 4-17       Device 245 Variable Camshaft Installation  	     4-63
 4-18       Device 246 Speed-Controlled EGR with Vacuum Advance
              Disconnect System Components 	     4-68
 4-19       Device 246 Speed-Controlled EGR with Vacuum Advance  Dis-
              connect Functional Schematic (Developer's Diagram) 	     4-68
 4-20       Device 246 Speed-Controlled EGR with Vacuum Advance  Dis-
              connect Installation (Developer Sketch)  	     4-77
 4-21       Device 246 Typical Installation on Retrofit Program  Test
              Vehicle	     4-77
 4-22       Device 172 Intake Manifold Modification (Developer Sketch)  . .     4-81
 4-23       Device 430 Intake Manifold Nozzle Screen Configuration ....     4-86
 4-24       Device 430 Intake Manifold Nozzle Screen Installation  ....     4-87
 4-25       Device 440 Intake Deflection Plate Vehicle Manufacturer
              Configurations 	     4-92
 4-26       Device 440 Intake Deflection Plate Installed and Typical
              Variations (Developer Sketch)  	     4-92
 4-27       Device 384 Air-Fuel Mixture Diffuser (Configuration  for
              Two-Barrel Carburetor) 	     4-97
 4-28       Device 384 Air-Fuel Mixture Diffuser Installation Sketch
              (from Developer's Patent Disclosure)  	     4-99
 4-29       Device 33 Carburetor Modification (Main Jet Differential
              Pressure) Configuration  	    4-104
 4-30       Device 33 Carburetor Modification (Main Jet Differential
              Pressure) Air-Fuel Ratio Test Results (Developer Data)  .  . .    4-106
 4-31       Device 56 Crankcase Blowby and Idle Air Bleed Modification
              (Developer Photo)	  .  . .    4-113
 4-32       Device 56 Special Air Bleed Idle Jet	    4-113
 4-33       Device 288 Carburetor Main Discharge Nozzle Modification  .  . .    4-117
 4-34       Device 295 Variable Venturi Carburetor  	    4-124
 4-35       Device 295 Variable Venturi Carburetor  Functional Diagram
              (Developer Sketch) 	    4-125
 4-36       Device 317 Carburetor Modification With Vacuum Advance
              Disconnect Installation (Developer Photo)  	    4-133
 4-37       Device 317 Carburetor Modification With Vacuum Advance
              Disconnect:   Principal Components (Developer Sketch)  ....    4-134
                                        C-9

-------
                                   VOLUME  II

                           ILLUSTRATIONS (CONTINUED)
Figure
 5-1        Device 69 Electronic-Controlled Vacuum Advance Disconnect
              with Carburetor Lean Idle Modification	      5-5
 5-2        Device 69 Electronic-Controlled Vacuum Advance Disconnect
              Functional Schematic (Developer Sketch)   	      5-6
 5-3        Device 175 Electronic Control Module Installed on Fender
              Well	     5-13
 5-4        Device 259 Photocell-Controlled Ignition System Components
              (4-Cylinder Ignition System) 	     5-25
 5-5        Device 259 Photocell-Controlled Ignition System Electrical
              Schematic (Developer Sketch) 	     5-27
 5-6        Device 259 Photocell Controlled Ignition System Typical
              Installation 	     5-29
 5-7        Device 268 Capacitive Discharge Ignition 	     5-32
 5-8        Device 268 Capacitive Discharge Ignition Schematic
              (Developer Sketch) 	     5-33
 5-9        Device 259 Ignition Timing and Spark Modification  	     5-37
 6-1        Device 52 Gaseous Fuel Carburetor Types  	      6-6
 6-2        Device 52 Single-Fuel System Diagram (Reference 35)   	      6-7
 6-3        Device 52 Dual-Fuel System Diagram (Reference  36)   	      6-7
 6-4        Device 52 Single-Fuel System Converter and  Carburetor
              Diagram (Reference 37)  	      6-9
 6-5        Device 52 Dual-Fuel System Converter and Carburetor  Diagram
              (Reference 38)	      6-9
 6-6        Device 52 LPG Conversion  Representative Carburetor
              (Reference 37)	     6-10
 6-7        Device 52 Variation of Air-Fuel Ratio with  Fuel Pressure
              (Engine:  Ford 352 CID with Type D - Reference 37)   	     6-11
 6-8        Effect of Air-Fuel Ratio  and Spark Advance  on  LPG
              Emissions (Reference 41)  	     6-14
 6-9        Device 52 Single-Fuel LPG Installation (Reference  52)   ....     6-25
 6-10        Device 459 LPG Conversion System Illustration  (Reference  66)  .     6-36
 6-11        Device 459 Single-Fuel Air  Valve Carburetor (Reference  66) .  .     6-36
 6-12        Device 460 Compressed Natural Gas Dual Fuel Conversion
              System  Installed on a Chrysler New Yorker (Reference  68) .  .     6-49
 6-13        CNG  Instrument Panel Controls (Reference 103)   	     6-51
 6-14        CNG  Dual-Fuel Conversion  System Functional  Schematic
              (Reference 46)	     6-51
 6-15        Device 282 LP Gas Injection System Components   	     6-68
 6-16        Device 282 LP Gas Injection Functional Schematic  	     6-68
 6-17        Device 279 Fuel Conditioner Functional Schematic  (Developer
              Data)	     6-78
 7-1        Device 24 System  Components (Developer Drawing)   	      7-4
 7-2        Device 170 Closed Blowby  Control System (Developer Drawing).  .      7-8
 7-3        Device 170 Closed Blowby  Control System Adjustable Blowby
              Flow and Pressure Relief  Valve (Developer Drawing)  	      7-8
 7-4        Device 170 Closed Blowby  Control System Adjustment Procedure  .     7-12
 7-5        Device 170 Closed Blowby  Control System Installation
              (Developer Photos)	„	     7-12
 7-6        Device 315  Closed Blowby  Control System Installed  on
              Carburetor	     7-16
                                       C-10

-------
                                    VOLUME II

                            ILLUSTRATIONS  (CONTINUED)
7-7        Device 315 Closed Blowby Control System Vent Valve
             Configuration (Based on Developer Drawings)  	    7-16
7-8        Device 315 Slide Mechanism (Based on Developer Drawings) ...    7-17
7-9        Device 160 Closed System with Filter Typical Installation
             (Developer Drawings) 	    7-21
7-10       Device 160 Closed Blowby Control System with Filter:  PCV
             Valve and Filter Assembly	    7-22
7-11       Device 160 Oil-Bath Type Air Cleaner for Open Blowby
             Systems (Developer Drawing)  	    7-22
7-12       Device 427 Closed Blowby Control System Filter-Valve
             Assembly	    7-27
7-13       Device 427 Closed Blowby Control System Filter-Valve
             Assembly Details (Developer Drawing) 	    7-28
7-14       Device 427 Closed Blowby Control System with Filter
             Functional Diagram (Developer Drawing) 	    7-28
8-1        Absorption-Regenerative Fuel Evaporation Control System  .  .  .     8-2
9-1        Device 165 Exhaust Gas Afterburner/Recirculation with
             Blowby and Fuel Evaporation Recirculation Installation .  .  .     9-6
9-2        Device 165 Exhaust Gas Afterburner/Recirculation with
             Blowby and Fuel Evaporation Recirculation Functional
             Block Diagram	     9-7
9-3        Device 408 Exhaust Gas and Blowby Recirculation with Intake
             Vacuum Control and Turbulent Mixing Assembly 	    9-16
9-4        Device 408 Exhaust Gas and Blowby Recirculation with Intake
             Vacuum Control and Turbulent Mixing Components 	    9-16
9-5        Exhaust Gas Recirculation System 	    9-22
9-6        Exhaust Particulate Matter Trapping System A	  .    9-22.
9-7        Cyclone Separator and Collection Box 	    9-23
                                      C-ll

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                                VOLUME  II

                                  TABLES
Table                                                                        Page

 1-1       Type of Vehicle Emission Controls  Incorporated  on Existing
             "Used Cars" at Time of Manufacture	       1-3
 1-2       Data Survey Results	       1-8
 2-1       Classification of Retrofit Methods	       2-3
 3-1       Type 1.1 - Exhaust Gas Control System Retrofit  Devices  ....       3-2
 3-2       Device 96 Catalytic Converter with Vacuum Advance Disconnect
             Emission Reduction and Fuel Consumption Performance   ....       3-8
 3-3       Device 96 Average Emission Reduction  Performance  . 	       3-8
 3-4       Device 96 Emission Reduction Performance Reported by
             Developer	       3-9
 3-5       Emission Test Results Obtained by  EPA on Tricomponent Cata-
             lytic Converter Provided by Device  96  Developer  	  .     3-10
 3-6       Device 96 Catalytic Converter with Vacuum Advance Disconnect
             Driveability Test Results  .	     3-13
 3-7       Device 96 Catalytic Converter with Vacuum Advance Disconnect
             Installation Procedure ....  	     3-15
 3-8       Device 96 Catalytic Converter with Vacuum Advance Disconnect
             Initial and Recurring Costs  	     3-18
 3-9       Device 292 LPG-Fuel Emission Reduction Performance Reported
             by Developer	     3-21
 3-10      Device 292 Catalytic Converter EPA Emission Test  Results  with
             Auxiliary Air Pump	     3-21
 3-11      Device 292 Catalytic Converter Emission  Reduction Reliability
             Reported by Developer for 48,300 Miles of Operation   ....     3-22
 3-12      Device 292 Catalytic Converter Installation Procedure   ....     3-24
 3-13      Device 292 Catalytic Converter Initial and Recurring Costs  .  .     3-25
 3-14      Device 62 Catalytic Converter EPA  Emission Test Results  .  .  .     3-27
 3-15      Device 93 Catalytic Converter with Exhaust Gas  Recirculation,
             Spark Modification, and Lean Idle Mixture EPA Emission
             Test Results	     3-30
 3-16      Composition of Candidate Alloys for Device 244  Rich Thermal
             Reactor	     3-34
 3-17      Device 244 Rich Thermal Reactor Developer Acceleration  Test
             Results	     3-45
 3-18      Device 244 Rich Thermal Reactor Developer Fuel  Consumption
             Test Results	     3-46
 3-19      Device 244 Rich Thermal Reactor Installation Procedure  ....     3-48
 3-20      Device 244 Rich Thermal Reactor Initial  and Recurring Costs   .     3-49
 3-21      Device 463 Rich Thermal Reactor Emission Levels Compared  to
             1975 Standards	     3-54
 3-22      Device 463 Rich Thermal Reactor Emission Levels Reported  by
             EPA	     3-54
 3-23      Device 463 Rich Thermal Reactor Exhaust  Backpressure Reported
             by Developer	     3-55
 3-24      Device 463 Rich Thermal Reactor Vehicle  Acceleration Time
             Increase Reported by Developer 	     3-55
                                    C-12

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                                  VOLUME  II
                              TABLES (CONTINUED)
Table                                                                        Page

 3-25      Device 468 Emission Test Results without Air Injection  ....     3-60
 3-26      Device 468 Emission Test Results with Air Injection   	     3-60
 3-27      Device 468 LTR-EGR Durability Emission Test  Results   	     3-61
 3-28      Device 468 LTR-EGR Fuel Consumption Compared to  Conventional
             Cars . -.-	     3-63
 3-29      Device 31 Turbine Blower and Conventional Air Pump System
             Emission Test Results (Developer 7-Mode Data)   	     3-67
 3-30      Device 31 Turbine Blower Air Injection System Installation
             Procedure	     3-70
 3-31      Device 31 Turbine Blower Air Injection System Initial and
             Recurring Costs  	     3-72
 3-32      Device 308 Exhaust Gas Afterburner Emission  Test Results
             Reported by Developer  	     3-75
 3-33      Device 308 Exhaust Gas Afterburner Installation  Procedure   .  .     3-77
 3-34      Device 308 Exhaust Gas Afterburner Initial and Recurring Costs     3-78
 3-35      Device 425 Exhaust Gas Afterburner Emission  Test Results
             Reported by Developer  	     3-81
 3-36      Device 425 Exhaust Gas Afterburner Installation  Procedure   .  .     3-85
 3-37      Device 425 Exhaust Gas Afterburner Initial and Recurring Costs     3-86
 3-38      Device 164 Exhaust Gas Filter Emission Test  Results  Reported
             by the Developer	     3-91
 3-39      Device 164 Exhaust Gas Filter Installation Procedure 	     3-92
 3-40      Device 164 Exhaust Gas Filter Initial and Recurring  Costs   .  .     3-93
 3-41      Device 322 Exhaust Gas Backpressure Valve Emission Test
             Results	     3-95
 4-1       Type 1.2 Induction Control System Retrofit Devices  	       4-2
 4-2       Device 1 Air Bleed to Intake Manifold Emission Results
             Reported by Developer  	       4-6
 4-3       Device 1 Air Bleed to Intake Manifold Emission Reduction and
             Fuel Consumption Performance 	       4-7
 4-4       Device 1 EPA Emission Test Results	       4-8
 4-5       Device 1 Air Bleed to Intake Manifold Driveability Test
             Results	       4-9
 4-6       Device 1 Air Bleed to Intake Manifold Installation Procedure  .     4-10
 4-7       Device 1 Air Bleed to Intake Manifold Initial and Recurring
             Costs	     4-13
 4-8       Device 42 Air Bleed to Intake Manifold Emission  Reduction  and
             Fuel Consumption Performance 	     4-17
 4-9       Device 42 Mean Emission Test Results Based on Tests  Reported
             by Developer	     4-17
 4-10      Device 42 Air Bleed to Intake Manifold Driveability  Test
             Results	     4-18
 4-11      Device 42 Air Bleed to Intake Manifold Installation  Procedure.     4-20
 4-12      Device 42 Air Bleed to Intake Manifold Initial and Recurring
             Costs	     4-21
 4-13      Device 57 Air Bleed with EGR and Vacuum Advance  Disconnect
             Emission Test Results Reported by Developer  	     4-25
 4-14      Device 57 Air Bleed with EGR and Vacuum Advance  Disconnect
             Installation Procedure 	     4-27
                                    C-13

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                                 VOLUME II
                              TABLES (CONTINUED)
Table                                                   •                     Page

 4-15      Device 57 Air Bleed with EGR and Vacuum Advance Disconnect
             Initial and Recurring Costs 	    4-29
 4-16      Device 325/433 Air-Vapor Bleed to Intake Manifold Emission
             Test Results Provided by Developer   	    4-34
 4-17      Device 325/433 Air-Vapor Bleed to Intake Manifold Average
             Percentage Emission Reduction 	    4-35
 4-18      Device 325/433 Air-Vapor Bleed to Intake Manifold Installation
             Procedure	    4-37
 4-19      Device 325/433 Air-Vapor Bleed to Intake Manifold Initial and
             Recurring Costs  	    4-38
 4-20      Device 401 Air-Vapor Bleed to Intake Manifold Emission Test
             Results Reported by Developer 	    4-40
 4-21      Device 401 Air-Vapor Bleed to Intake Manifold Installation
             Procedure	    4-41
 4-22      Device 401 Air-Vapor Bleed to Intake Manifold Initial and
             Recurring Costs  	    4-42
 4-23      Device 418 Air Bleed to Intake Manifold Mean Emission Test
             Results	    4-44
 4-24      Device 458 Air Bleed to Intake Manifold Emission Test Results .    4-45
 4-25      Device 462 Air Bleed to Intake and Exhaust Manifolds Mean
             Emission Test Results	    4-48
 4-26      Device 10 Throttle-Controlled EGR with  Vacuum Advance Dis-
             connect Emission Reduction and Fuel Consumption Performance .    4-52
 4-27      Device 10 Throttle-Controlled EGR with  Vacuum Advance Dis-
             connect Driveability Test Results 	    4-53
 4-28      Device 10 Throttle-Controlled EGR with  Vacuum Advance Dis-
             connect Installation Procedure  	    4-55
 4-29      Device 10 Throttle-Controlled EGR with  Vacuum Advance Dis-
             connect Initial  and Recurring Costs  	    4-56
 4-30      Device 245 Variable Camshaft Emission Reduction and Fuel Con-
             sumption Performance	    4-60
 4-31      Comparative Emission Test  Results  for a  Device Tested by EPA
             with Variable Camshaft Timing, Vacuum Advance Disconnect and
             Lean Carburetion	    4-61
 4-32      Device 245 Driveability Test Results	    4-62
 4-33      Device 245 Variable Camshaft Timing Installation Procedure  . .    4-64
 4-34      Device 245 Variable Camshaft Timing Initial and Recurring Costs    4-66
 4-35      Device 246 Speed-Controlled EGR with Vacuum Advance Disconnect
             Emission Reduction and Fuel Consumption Performance 	    4-70
 4-36      Device 246 Speed-Controlled EGR with Vacuum Advance Disconnect
             Emission Test Results Reported by Developer 	    4-71
 4-37      Device 246 Speed-Controlled EGR with Vacuum Advance Disconnect
             Emission Test Results Reported by EPA	    4-72
 4-38      Device 246 Speed-Controlled EGR with Vacuum Advance Disconnect
             Driveability Test Results  	    4-73
 4-39      Device 246 Speed-Controlled EGR with Vacuum Advance Disconnect
             Installation Procedure  	    4-75
 4-40      Device 246 Speed-Controlled EGR with Vacuum Advance Disconnect
             Initial and  Recurring Costs 	    4-78
                                    C-14

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                                 VOLUME II

                              TABLES (CONTINUED)


Table                                                                        Page

 4-41      Device 294 Emission Test Results	    4-79
 4-42      Device 172 Intake Manifold Modification Emission  Test  Results
             Reported by Developer 	    4-82
 4-43      Device 172 EPA Emission Test Results	    4-82
 4-44      Device 172 Intake Manifold Modification Fuel Consumption Data
             Reported by Developer 	    4-83
 4-45      Device 172 Intake Manifold Modification Installation Procedure.    4-84
 4-46      Device 172 Intake Manifold Initial and  Recurring  Costs  ....    4-85
 4-47      Device 430 Induction Modification Emission Test Results Pro-
             vided by Developer	    4-88
 4-48      Device 430 Induction Modification Installation Procedure   .  .  .    4-89
 4-49      Device 430 Induction Modification Initial  and Recurring Costs  .    4-90
 4-50      Device 440 Intake Deflection Plate Test Experience  Summary
             Provided by Developer 	    4-93
 4-51      Device 440 Intake Deflection Plate Installation Procedure  .  .  .    4-95
 4-52      Device 440 Intake Deflection Plate Initial and Recurring Costs.    4-96
 4-53      Summary of Device 384 Air-Fuel  Mixture  Diffuser Exhaust
             Emission Data Provided by Developer  	   4-100
 4-54      Device 384 Air-Fuel Mixture Diffuser Installation Procedures.  .   4-102
 4-55      Device 33 Carburetor Modification (Main Jet Differential Pres-
             sure) Emission Test Results Reported  by  Developer 	   4-107
 4-56      Device 33 Carburetor Modification (Main Jet Differential Pres-
             sure) Emission Reduction and  Fuel Consumption Performance  .  .   4-107
 4-57      Device 33 Carburetor Modification (Main Jet Differential
             Pressure)	   4-109
 4-58      Device 33 Installation Procedure  	  ....   4-109
 4-59      Device 33 Initial and Recurring Costs  	   4-111
 4-60      Device 56 Crankcase Blowby and  Idle Air Bleed Modification:
             Summary of Exhaust Emission Data Reported by Developer   .  .  .   4-114
 4-61      Device 56 Installation Procedure  	   4-115
 4-62      Device 56 Initial and Recurring Costs  	   4-116
 4-63      Device 288 Carburetor Main Discharge Nozzle Modification
             Emission Reduction and Fuel Consumption  Performance  	   4-118
 4-64      Device 288 Summary of Developer-Reported Measurements  by
             Independent Laboratories  	   4-119
 4-65      Device 288 Carburetor Main Discharge Nozzle Modification
             Driveability Test Results 	   4-120
 4-66      Device 288 Carburetor Main Discharge Nozzle Modification
             Installation Procedure  .	   4-121
 4-67      Device 288 Carburetor Main Discharge Nozzle Modification
             Initial and Recurring Costs 	   4-122
 4-68      Device 295 Variable Venturi Carburetor  Emission Reduction  and
             Fuel Consummation Performance 	   4-128
 4-69      Device 295 Variable Venturi Carburetor  Driveability Test
             Results	   4-129
 4-70      Device 295 Variable Venturi Carburetor  Installation Procedure  .   4-130
 4-71      Device 295 Variable Venturi Carburetor  Initial and  Recurring
             Costs	   4-131
 4-72      Device 317 Emission Test Results Reported  by Developer ....   4-135
                                   C-15

-------
                                VOLUME II
                             TABLES  (CONTINUED)
          Device 317 Carburetor Modification with Vacuum Advance Dis-
            connect Installation Procedure  	 	   4-137
          Device 317 Carburetor Modification with Vacuum Advance Dis-
            connect Installation Costs  	 	   4-138
4-75      Device 100 Turbocharger Emission Test Results 	   4-139
4-76      Device 22 Electronic Fuel Injection Emission Test Results
            Reported by EPA	   4-141
4-77      Device 22 Electronic Fuel Injection Acceleration Results  . .  .   4-142
5-1       Type 1.3 Ignition Control System Retrofit Devices 	     5-1
5-2       Device 69 Electronic-Controlled Vacuum Advance Disconnect and
            Carburetor Lean Idle Modification Emission Reduction and Fuel
            Consumption Performance 	 	     5-7
5-3       Device 69 Driveability Test Results	     5-8
5-4       Device 69 Electronic-Controlled Vacuum Advance Disconnect and
            Carburetor Lean Idle Modification Installation Procedure  .  .     5-9
5-5       Device 69 Electronic-Controlled Vacuum Advance Disconnect and
            Carburetor Lean Idle Modification Initial and Recurring Costs    5-11
5-6       Device 175 Ignition Timing Modification with Lean Idle Adjust-
            ment Emission Test Results Submitted by Developer 	    5-14
5-7       Device 175 Ignition Timing Modification with Lean Idle Adjust-
            ment Emission Reduction and Fuel Consumption Performance  .  .    5-15
5-8       Device 175 Driveability Test Results	    5-17
5-9       Device 175 Installation Procedure 	    5-18
5-10      Device 175 Initial and Recurring Costs  	    5-19
5-11      Device 23 Electronic Ignition Unit Emission Test Results Re-
            ported by HEW/NAPCA	    5-22
5-12      Device 95 Ignition Spark Modification Emission Test Results .  .    5-23
5-13      Device 95 Emission Test Results	    5-24
5-14      Device 259 Photocell-Controlled Ignition System Installation
            Procedure	    5-30
5-15      Device 259 Photocell-Controlled Ignition System Initial and
            Recurring Costs 	    5-31
5-16      Device 268 Capacitive Discharge Ignition Installation Procedure    5-34
5-17      Device 268 Capacitive Discharge Ignition Initial and Recurring
            Costs	    5-35
5-18      Device 296 Ignition Timing and Spark Modification Emission Test
            Results Reported by Developer ..... 	    5-38
5-19      Device 296 Ignition Timing and Spark Modification Installation
            Procedure	    5-39
5-20      Device 296 Ignition Timing and Spark Modification Initial and
            Recurring Costs 	    5-39
6-1       Type 1.4 Fuel Modification Retrofit Devices	     6-2
6-2       Device 52 LPG Conversion Emission Test Results with 1968 Buick
            Skylark	    6-12
6-3       Device 52 LPG Conversion Emission Test Results with Vacuum
            Advance Disconnect and Retarded Timing on 1970 Falcons and
            Rebels  	  .....    6-12
6-4       Device 52 Emission Test Results with Ford Fairlane and
            Mustang	    6-13
                                    C-16

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                                    VOLUME  II
                               TABLES  (CONTINUED)
6-5        Device 52 LPG Conversion Emission Data  Obtained by California
             Gaseous Fuel Test Procedure	    6-15
6-6        Device 52 LPG Conversion Vehicle Maintenance  Cost
             Comparison	    6-17
6-7        Device 52 LPG Conversion Acceleration Test  Results with  Spark
             Retard and Vacuum Advance Disconnected   	    6-18
6-8        Device 52 LPG Conversion Fuel Consumption Comparison   	    6-19
6-9        Device 52 LPG Conversion Installation Procedure  	    6-21
6-10       Device 52 LPG Conversion Initial and Recurring Costs  for
             Typical Conversion to Meet Emission Standards  	    6-26
6-11       Device 466 LPG Gasoline Dual-Fuel Conversion  Emission Test
             Results	    6-32
6-12       Device 466 Exhaust Hydrocarbon Composition  by Subtractive
             Column Analysis	    6-32
6-13       Device 466 Emission Test Results	    6-33
6-14       Device 459 LPG Conversion with Deceleration Unit Emission Test
             Results	    6-37
6-15       Device 461 Emission Test Results	    6-40
6-16       Device 464 Emission Test Results	    6-44
6-17       Compressed Natural Gas Tank Characteristics 	    6-48
6-18       Device 460 Compressed Natural Gas Dual-Fuel Conversion Emission
             Test Results	    6-50
6-19       Device 460 CNG Dual-Fuel Conversion Emission  Test Results  .  .  .    6-52
6-20       Device 460 CNG Hydrocarbon Reactivity 	    6-52
6-21       Device 460 Acceleration Test Results with a 1971 Ford
             Mustang	    6-55
6-22       Device 460 CNG Dual-Fuel Conversion Initial and Recurring
             Costs	    6-57
6-23       Device 182 Fuel and Oil Additives Emission  Test Results
             Reported by City of Los Angeles	    6-62
6-24       Device 182 Fuel and Oil Additives Emission  Test Results
             Reported by Olson Laboratories  	    6-62
6-25       Device 182 Fuel Consumption Reduction Reported by McDonnell
             Douglas Aircraft Division 	    6-63
6-26       Device 182 Fuel and Oil Additives Initial and Recurring  Costs  .    6-64
6-27       Device 465 Emission Test Results	    6-66
6-28       Device 282 LP Gas Injection Installation Procedure   ......    6-71
6-29       Device 282 LP Gas Injection Initial and Recurring Costs  ....    6-72
6-30       Device 36 Fuel Conditioning by Exposure to  Electromagnetic Field
             Emission Test Results	    6-77
6-31       Device 279 Fuel Conditioner Emission Test Results Reported by
             Developer	    6-79
6-32       Device 279 Fuel Conditioner Installation Procedure   	    6-80
6-33       Device 279 Initial and Recurring Costs   	    6-81
7-1        Group 2 Crankcase Emission Control Systems   	      7-2
7-2        Device 24 Heavy Duty Positive Crankcase Control Valve with Air
            •Bleed Exhaust Emission Test Results Reported by EPA 	      7-4
7-3        Device 24 Heavy Duty Positive Crankcase Ventilation with Air
             Bleed Initial and Recurring Costs 	      7-5
                                       C-17

-------
                                    VOLUME II
                                TABLES (CONTINUED)
Table
 7-4       Device 170 Closed Blowby Control System Exhaust  Emission Test
             Results	     7-10
 7-5       Device 170 Closed Blowby Control System Installation
             Procedure	     7-13
 7-6       Device 170 Closed Blowby Control System Initial  and  Recurring
             Costs	     7-14
 7-7       Device 315 Closed Blowby Control System Exhaust  Emission Test
             Results Reported by Developer 	     7-18
 7-8       Device 315 Closed Blowby Control System Installation
             Procedure	     7-19
 7-9       Device 315 Closed Blowby Control System Initial  and  Recurring
             Costs . ,	     7-20
 7-10      Device 160 Closed or Open Blowby Control System  with Filter
             Emission Test  Results  Reported by Developer  	     7-23
 7-11      Device 160 Closed Blowby Control System with Filter  Installa-
             tion Procedure	     7-25
 7-12      Device 160 Closed Blowby Control System with Filter  Initial and
             Recurring Costs 	     7-26
 7-13      Device 427 Closed Blowby Control System with Filter  Exhaust
             Emission Reduction Performance  	     7-29
 7-14     .Device 427 Closed Blowby Control System with Filter  Drive-
             ability Results Reported by Developer 	     7-30
 7-15      Device 427 Closed Blowby Control System with Filter  Installa-
             tion Procedure	     7-32
 7-16      Device 427 Closed Blowby Control System with Filter  Initial
             and Recurring  Costs	     7-33
 8-1       Device 467 Absorption-Regenerative Fuel Evaporation  Control
             System  Installation  Procedure 	  .....     8-4
 8-2       Device 467 Absorption-Regenerative Fuel Evaporation  Control
             System  Initial and Recurring  Costs   	     8-5
 9-1       Group 4 Emission Control Combination Retrofit Devices  	     9-1
 9-2       Device 59 Three-Stage  Exhaust Gas Control System Emission
             Test Results	     9-2
 9-3       Device 59 Three-Stage  Exhaust Gas Control System Driveability  .     9-3
 9-4       Device 165 Exhaust Gas Afterburner/Recirculation with  Blowby
             and Fuel Evaporation Recirculation Exhaust Emission  Test
             Results	     9-8
 9-5       Device 165 Exhaust Gas Afterburner/Recirculation with  Blowby
             and Fuel Evaporation Recirculation Driveability  	     9-9
 9-6       Exhaust Gas Afterburner/Recirculation with Blowby  and  Fuel
             Evaporation Recirculation Installation Procedure  	     9-11
 9-7       Exhaust Gas Afterburner/Recirculation with Blowby  and  Fuel
             Evaporation Recirculation Initial and  Recurring  Cost   ....     9-13
 9-8       Device 408 Exhaust Gas and Blowby Recirculation with Intake
             Vacuum  Control  and Turbulent Mixing Driveability   	     9-18
 9-9       Device 408 Exhaust Gas and Blowby Recirculation with Intake
             Vacuum  Control  and Turbulent Mixing Installation
             Procedure	     9-19
                                       C-18

-------
                                   VOLUME   II
                                TABLES (CONTINUED)
Table                                                                        Page

 9-10      Device 408 Exhaust Gas and Blowby Recirculation with  Intake
             Vacuum Control and Turbulent Mixing Initial and  Recurring
             Costs	    9-20
 9-11      Device 469 Emission Reduction Results Cold 9  Cycle CVS   ....    9-24
                                       C-19

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                                     VOLUME III
                                  TABLE  OF  CONTENTS


Section                                                                        Page

            FOREWORD	       iii

            ACKNOWLEDGMENTS  	         v

            GLOSSARY	        vi

   1        INTRODUCTION 	       1-1

            1.1      Evaluation Objectives  	       1-1
            1.2      Evaluation Approach 	       1-2
            1.3      Evaluation Conclusions  	       1-2

   2        RETROFIT METHOD APPLICABILITY TO  USED  CAR  EMISSION CONTROL  .  .       2-1

            2.1      The Impact of Retrofit Controls on Used Vehicles   .  .       2-1
            2.2      Retrofit  System Emission Control  Capability  	       2-2

   3        EVALUATION METHODOLOGY	       3-1

            3.1      The Criteria  Index	       3-2
            3.1.1    Emission  Standards  Factor 	       3-4
            3.1.2    Emission  Baseline Factor  	       3-4
            3.1.3    Safety Factor	       3-4
            3.1.4    Critical  Driveability  Factor   	  ...       3-5
            3.1.5    General Driveability Factor  	       3-5
            3.1.6    Installation  Cost Factor	       3-6
            3.1.7    Recurring Cost Factor	       3-6
            3.1.8    Reliability Factor   	       3-6
            3.1.9    Maintainability Factor  	       3-6
            3.1.10   Availability  Factor 	       3-7
            3.2      Performance Index  	       3-7
            3.2.1    Emission  Index	       3-8
            3.2.2    Driveability  Index   	       3-9
            3.2.3    Cost Index	      3-10
            3.3      Cost Effectiveness  Index	      3-12
            3.4      Establishing  Weighting Coefficients  for the
                       Performance Index 	      3-12

   4        RETROFIT PERFORMANCE ANALYSIS  	       4-1

            4.1      Engineering Analysis	       4-1
            4.1.1    Engineering Analysis Team	       4-1
            4.1.2    Engineering Analysis Approach  	       4-2
            4.2      Test Program	       4-4
            4.2.1    Test Vehicle  Fleet	       4-4
            4.2.2    Selection of  Retrofit  Test Devices	       4-8
            4.2.3    Test Approach	       4-8
            4.2.4    Test Procedures	      4-12
            4.3      Performance Analysis Data  Inputs  and Results   ....      4-13
                                       C-21

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                                    VOLUME III
                                CONTENTS (CONTINUED)


Section                                                                         Page

   5        CRITERIA INDEX ANALYSIS  	        5-1

            5.1      Evaluation Criteria 	        5-1
            5.2      Criteria  Index Results   	        5-1
            5.3      Retrofit  System Feasibility 	        5-5

   6        PERFORMANCE INDEX  ANALYSIS 	        6-1

            6.1      Emission  Reduction Results   .  .  .  .	        6-1
            6.1.1    Device 1:   Air Bleed to  Intake Manifold	        6-8
            6.1.2    Device 96:  Catalytic Converter  with  Vacuum
                       Advance Disconnect  	        6-9
            6.1.3    Device 175:   Ignition Timing Modification  with
                       Lean Idle Adjustment	       6-11
            6.1.4    Device 246;   Exhaust Gas Recirculation with Vacuum
                       Advance Disconnect  	       6-11
            6.1.5    Emission  Reduction Versus Engine Size 	       6-12
            6.1.6    Emission  Index Results   	       6-12
            6.2      Driveability Index  	       6-12
            6.2.1    Driveability Index Results   	       6-15
            6.2.2    Driveability Index Sensitivity Analysis  	       6-18
            6.3      Cost Index	       6-18
            6.3.1    Initial Costs	       6-19
            6.3.2    Recurring Costs	       6-19
            6.3.3    Cost Index Results	       6-20
            6.3.4    Cost Index Sensitivity Analysis  	       6-22
            6.4      Performance Index 	       6-23
            6.4.1    Performance Index Results 	       6-24
            6.4.2    Weighting Coefficient Sensitivity Analysis  	       6-24

   7        COST EFFECTIVENESS INDEX 	        7-1

            7.1      Cost Effectiveness Results	        7-1

   8        GUIDELINES FOR SELECTING AND IMPLEMENTING RETROFIT  METHODS .  .        8-1

            8.1      Defining  the Required Emission Reduction  	        8-2
            8.2      Defining  the Uncontrolled Vehicle Population  ....        8-2
            8.3      Identifying Candidate Retrofit Methods   	        8-3
            8.4      Determining Cost Effective  Retrofit  Methods 	        8-5
            8.5      Defining  the Certification  Program  	        8-7
            8.6      Cost Effectiveness Studies  of  Alternative  Control
                       Programs	        8-8
            8.7      Preparing an Implementation Plan	        8-8
            8.8      Implementing the Plan	        8-9

   9        RECOMMENDATIONS  	        9-1

  10        REFERENCES	       10-1
                                        C-22

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                                     VOLUME III

                                 CONTENTS  (CONTINUED)


Appendix                                                                        Page

    A        Baseline Exhaust  Emissions  for Test  Vehicles  Prior  to  Each
               Retrofit Test  (1972  Federal Test Procedure  Grams/Mile)  .  .  .       A-l

    B-l      Retrofit Program  Test  Schedule 	       B-l

    B-2      Retrofit Program  Test  Summary Versus Contract Requirements  .  .       B-l

    C        Devices  Evaluated in Retrofit Program  	       C-l

    D        Performance Analysis Input  Data   	       D-l

    E        Computer Analysis Results	       E-l

    F        Baseline and  Retrofit  Emission Levels in Grams/Mile  for
               Devices Tested  in  Retrofit  Program by 1972  Federal Test
               Procedure	       F-l

    G        Mean  Emission Levels for Retrofit  Devices  Evaluated Based
               on  EPA and  Retrofit  Developer Test Data	       G-l

    H        Welch's  Approximate  t  Solution of  the Fisher-Behrens Problem  .       H-l

    J        Sensitivity Analysis of Retrofit Program Driveability  and
               Cost Indexes	       J-l

    K        Cost  Index Results for Retrofit Devices with  Cost Data  ....       K-l

    L        Fuel  Consumption  Measured During the 1972  Test  for Devices
               Tested in the Retrofit Program 	       L-l
                                   ILLUSTRATIONS


Figure                                                                          Page

  2-1      Sources  and  Quantities  of  Emissions  from an  Uncontrolled
             Vehicle	     2-3
  4-1      Baseline and Retrofit  System Test  Sequence for  Each  Test
             Vehicle	    4-11
  6-1      Mean Percentage Emission Reduction and  90 Percent  Confidence
             Limits for Exhaust Emission Control Retrofit  Systems  Tested
             at Anaheim,  California,  and Taylor, Michigan  	     6-9
  8-1      Typical  Example of  Program Management Structure for  Periodic
             Vehicle Inspection Program .  .	    8-10
                                         C-23

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                                   VOLUME  III

                                      TABLES


Table                                                                          Page

 2-1      Estimated Percentage of Vehicle Population that Could be
            Retrofitted with Emission Control Systems	     2-3
 2-2      Potential Pollutant Control Capability of Retrofit Methods  by
            Generic Groups 	     2-5
 3-1      Performance Parameters and  Evaluation Criteria 	     3-3
 3-2      Weighting Coefficients for  the Performance Index 	    3-14
 4-1      Test Vehicle Fleet	     4-5
 4-2      Test Fleet Exhaust Emissions 	     4-6
 4-3      Taylor vs Anaheim Test Vehicle Baseline Emission Level
            Differences in Mean Grams/Mile (Based on Appendix A) 	     4-9
 4-4      Retrofit Devices Selected for Test Programs	    4-10
 5-1      Criteria Index Results for  Devices Evaluated  in Retrofit Program .     5-2
 6-1      Percentage Emission Reduction of Devices Tested in Retrofit
            Program	     6-3
 6-2      Average Percentage Exhaust  Emission Reduction by Test
            Procedure for Devices Evaluated in Retrofit Program	     6-6
 6-3      Discriminatory Power of t Tests	     6-8
 6-4      Mean Percentage Emission Reduction and 90 Percent Confidence
            Intervals for Exhaust Emission Control Retrofit Systems
            Tested at Anaheim, California and Taylor, Michigan 	     6-9
 6-5      Rank Ordered Emission Index Values by Test Method for Retrofit
            Devices Evaluated	    6-13
 6-6      Weighting Factors  Used for  General Driveability Index
            Calculations 	    6-15
 6-7      Driveability Index Results  in Rank Order for  Devices Tested in
            Retrofit Program 	    6-16
 6-8      Sensitivity Analysis Calculation  for  the Driveability Index  .  .  .    6-18
 6-9      Average Fuel Mileage Change for Exhaust Emission Control
            Retrofit Systems Tested at Anaheim,  California,  and Taylor,
            Michigan	    6-20
 6-10     Cost Index in Order of Rank for Retrofit Devices with Cost  Data   .    6-21
 6-11     Cost Index Sensitivity Analysis Results  	    6-23
 6-12     Mean Performance Index Results  in Rank Order  for Devices Tested
            in Retrofit Program  	    6-25
 6-13     Performance Index  with Alternate  Weighting Coefficients  for
            Devices  Tested in Retrofit Program 	    6-27
 7-1      Cost Effectiveness Index in Order of  Rank for Retrofit Devices
            with  Cost and  Emission Data	     7-3
 8-1      Light Duty Vehicle Population and  Type  of Emission Control  ....     8-4
 8-2      Performance Parameters  and  Evaluation  Criteria  	     8-6
                                      C-24

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                                    VOLUME IV

                                     CONTENTS
Section                                                                      Page

            FOREWORD	      iii

            ACKNOWLEDGMENTS  	  ......  	       v

            GLOSSARY .	o  ....  o  .....      vi

   1        INTRODUCTION	      1-1

            1.1  Program Objectives	...<>...      1-1
            1.2  Program Approach	„...	      1-1
            1.3  Program Schedule	      1-2
            1.4  Program Organization	      1-3

   2        RETROFIT METHOD SURVEY 	  .  	      2-1

            2.1  Survey Approach ...............  	      2-1
            2.2  Recording System  ....................      2-4
            2.3  Retrofit Method Classification System ..........      2-5

   3        SYSTEM TESTS „	      3-1

            3.1  Identification of Candidate Retrofit Systems for Test  .  .      3-2
            3.2  Test Vehicle Selection	  .      3-3
            3.3  Retrofit Device Emission Tests  	  .......      3-9
            3.4  Driveability Tests	    3-10
            3.5  Durability Tests  	  ...........    3-12
            3.6  Facilities		    3-14

   4        SYSTEM DESCRIPTIONS  	      4-1

            4.1  System Description Outline  	      4-1
            4.2  Approach to Performance  Parameter  Analyses  .  .  	      4-4

   5        PERFORMANCE ANALYSIS ........ 	  .  .  	      5-1

            5.1  Performance Index Equation	      5-1
            5.2  Methodology Implementation  	      5-3

Appendix

   A        Request for Retrofit Source Identification 	      A-l
   B        Letter of Inquiry to Retrofit Developers  	      B-l
                                        C-25

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                                      VOLUME IV

                                 CONTENTS (CONTINUED)

  Appendix                                                                       Page

    C        News Release	   C-l
    D        Retrofit Data Questionnaire and Transmittal Letter 	   D-l
    E        Excerpts from California Health and Safety Code Applicable
             to Retrofit Methods for Vehicle Emission Control 	   E-l
    F        California Blowby Device Test Procedure  	   F-l
    G        AMA Driveability Procedure 	   G-l
    H        Computer Program Printout for Analytical Methodology 	   H-l


                                   ILLUSTRATIONS

 Figure                                                                          Page

  1-1        Program Approach to Determining Effectiveness and
             Costs of Retrofit Methods	   1-2
  1-2        Program Master Schedule  	   1-3
  1-3        Program Organization Structure 	   1-4
  2-1        Data Survey Record Sheet '	   2-4
  3-1        Test Vehicle Procurement Screening Data Sheet  	   3-6
  3-2        Representative Test Vehicles	   3-7
  3-3        Baseline and Retrofit  System  Test  Sequence for
             Each Test Vehicle	3-11
  3-4        Los Angeles Durability Test Route	3-13
  3-5        Daily Shift Record for Durability  Test  	  3-15
  3-6        Vehicle Emission Test  Facility at  Anaheim,  California  	  .  3-16
  3-7        Driveability Test Area	3-16
  3-8        Olson Laboratories Emission Test Equipment  	  3-17
  5-1        Retrofit Information Flow to  Computer   	   5-5
  5-2        Exhaust Emissions Computer Input Sheet  	   5-6
  5-3        Driveability Test Data Input  Sheet	   5-7
  5-4        Retrofit Device Data-Input Form	   5-8
  5-5        Computer Program Top Level Flow Chart   	  5-10


                                        TABLES

 Table                                                                            Page

  2-1         Retrofit Method  Program  News  Release Mailing  List   	   2-3
  2-2         Classification  of Retrofit  Methods 	  ...   2-6
  3-1         Test  Vehicle  Fleet	   3-6
  3-2         Retrofit Test Vehicle  Service  and  Tuneup  Procedure  	   3-8
  3-3         Durability  Test  Route	  3-14
  3-4         Durability  Test  Mileage  Accumulation Schedule  	  3-14
  4-1         Retrofit Method  Performance Parameter Evaluation Matrix   	   4-2
.  4-2         Device  No.       Performance Characteristics   	   4-3
  4-3         Installation  Procedures:  Device No.         	   4-6
  4-4         Installation  Cost: Device No.        	   4-7
  5-1         Performance Parameters and  Evaluation Criteria  	   5-4
                                         C-26

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                                     VOLUME V

                                     CONTENTS


Appendix                                                                     Page

            FOREWORD	o«..      iii

            ACKNOWLEDGMENTS  	       v

            GLOSSARY 	  ........      vi

  V-l       DATA SURVEY RESULTS  .	„  .    V-l-1

  V-2       INVENTORY OF RETROFIT SOURCE DATA	    V-2-1

  V-3       DATA SURVEY:  QUESTIONNAIRE RESPONSES   ............    V-3-1

  V-4       ALPHABETICAL INDEX - DEVELOPMENT SOURCES  OF RETROFIT
              DEVICES EVALUATED  .  .  .	    V-4-1
                                        C-27

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                                    VOLUME VI

                                     CONTENTS


Section                                                                       Page

            FOREWORD	„	,	      iii

            ACKNOWLEDGMENTS  „	„	        v

            GLOSSARY	o	       vi

   1        SUMMARY AND CONCLUSIONS  	      1-1

            1.1  Summary of Test Results	      1-1
            1.2  Conclusions	      (1)

   2        INTRODUCTION	      2-1

            2.1  Background	      2-1
            2.2  Objectives	      (1)

   3        DURABILITY TEST PROGRAM  	      3-1

            3.1  Test Vehicles	      3-1
            3.2  Description of Devices  	 ..........      (1)
            3.3  Vehicle Preparation and Maintenance ...........      (1)
            3.4  Device Installation and Maintenance 	      (1)
            3.5  Test Route and Driving Schedule	      (1)
            3.6  Emission Test Procedures  .	      (1)

   4        TEST RESULTS AND DISCUSSION	      4-1

            4.1  Test Results	      4-1
            4.2  Discussion of Results	      (1)

Appendices	      (1)
(1)  Missing page numbers were not established at the time of printing of this
     volume; Volume VI to be published shortly.
                                        C-29

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