77-14 CH
Test Results of a Dodge Dart
Equipped with the Holley Sonic Carburetor
December 1977
Technology Assessment and Evaluation Branch
Emission Control Technology Division
Office of Mobile Source Air Pollution Control
Environmental Protection Agency
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Abstract
Under EPA contract, the Holley Carburetor Division of Colt Industries
developed an application of the Dresser sonic carburetor design for
evaluation by EPA. The Holley sonic carburetor was tested for emissions
and fuel economy in a 1975 California model Dodge Dart with a 3.7 litre
(225 cu in.) six cylinder engine. The test results were compared to
those of the same vehicle in baseline condition (production carburetor
and emission control system).
Factors such as the air/fuel ratio, idle enrichment, and air injection
were varied to optimize the emissions. After an optimum setting was
found, the emissions were still generally higher than the same vehicle
in baseline condition. Addition of a three-way catalyst reduced NOx
below baseline, but HC, fuel economy and especially CO values were still
greater than baseline.
Conclusions
1) There were no configurations tested for which the sonic carbureted
vehicle was able to achieve emissions and fuel economy results comparable
to the same vehicle in production configuration.
2) The sonic carburetor operating in conjunction with the other emission
control devices, including the oxidation catalyst, was able to maintain
emission levels within the 1977 Federal Standards.
3) '75 FTP results with the three-way catalyst installed (CO 15-30
g/mi; NOx 0.2-0.5 g/mi; fuel economy 14.5-16 mpg) as well as very low
emission levels in steady state tests (Tables 2, 4, 5) indicate the
following problem areas:
A) The time averaged mixture entering the engine during a non-
steady state driving cycle may be much richer than indicated
by the air/fuel trim setting alone. This could be caused by
the vacuum actuated power enrichment system as well as the
accelerator pump operation.
B) During non-sonic operation (low manifold vacuum) the air/fuel
ratio becomes more variable and the fuel distribution less
uniform. These conditions are due to varying air velocity
through the carburetor venturi and lack of a sonic shock wave
to break up the fuel droplets.
C) The EGR rate appears to be much greater than necessary for
operation with the three-way catalyst.
These factors are all aggravated by high load operation, which occurs
often due to the low power/weight ratio of this vehicle.
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4) Driveability of the test vehicle with the sonic carburetor was
considered to be poor. Holley's test of the vehicle in baseline con-
dition indicated that it also had poor driveability. The sonic carburetor
cannot, therefore, be considered to be the source of the driveability
problem. Additionally, it should be noted that the sonic carburetor
did not improve driveability.
5) This test program covered a wide range of carburetor/emission
control configurations, but a program of much larger scope would be
necessary to determine with certainty the maximum capabilities and
specific weaknesses of the sonic carburetor.
Background
EPA's Emission Control Technology Division is interested in evaluating
systems which offer potential for emissions reduction or improvement
in fuel economy compared to conventional engines and vehicles because of
the obvious benefits to the Nation from the identification of such systems.
In those cases in which review by EPA technical staff suggests that the
data available show promise for a new system, tests are performed at
the EPA Motor Vehicle Emission Laboratory at Ann Arbor, Michigan. The
results of all such tests are set forth in a series of Technology Assess-
ment and Evaluation Reports, of which this report is one.
Induction systems are one of the focal points in the search for better
fuel economy and lower emissions. This is because precise control of
the inlet mixture allows greater control of the exhaust emissions as
well as improved fuel economy.
The subject of this report is a carburetor concept developed by Dresser
Industries and patented as the Dresserator Inductor. EPA wished to
evaluate this concept because of (1) its claimed ability to provide a
constant, homogeneous air/fuel mixture over a wide range of engine
operating conditions and (2) its demonstrated capability on Dresser
prototypes (TAEB test report 75-7AW). Holley Carburetor Division of
Colt Industries was awarded a contract by EPA to develop a complete
vehicle/carburetor/ emission control package based on Dresser's design.
For a test vehicle, Holley chose a 1975 Dodge Dart with a six cylinder
engine and California emission controls. Holley then built a sonic
carburetor specifically for use on the test vehicle, while also modi-
fying the EGR system to be compatible with the new carburetor. All
other engine calibrations, including the ignition system and valve
timing, were left in baseline condition.
After Holley completed development and testing of the modified vehicle,
it was sent to the EPA for the testing described in this report.
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System Description
The test vehicle was a 1975 Dodge Dart powered by a 3.7 litre (225 cu
in.) six cylinder engine with an automatic transmission. The vehicle
was calibrated to California specifications, so the emission control
system consisted of an air pump, EGR, and oxidation catalyst. Prelimi-
nary testing with the sonic carburetor retained these components, although
the EGR had been modified to be back pressure controlled. Subsequent
tests were conducted with other configurations as described in the test
procedures.
The following is a description of the sonic carburetor from the Holley
report:
"Functionally, this carburetor is shown in block diagram form in
Figure 2.* The following work description will help clarify the
functions.
The air section is based on the Dresser Industries Model III variable
area venturi. The venturi throat is rectangular in cross-section
with one dimension of the throat fixed and the other variable with
throttle position. The movable surface and the side opposite are
essentially flat surfaces. A contoured shape is designed into the
remaining two surfaces to form a venturi. In this design, there is
a constant ratio of throat area to inlet area over the complete
operating range.
The fuel metering and distribution bar, located upstream of the
venturi throat, has tapered fuel metering slots that also aid fuel
distribution and fuel atomization in the venturi air section. The
fuel bar is attached to the movable venturi section such that
travel of the fuel bar is identical to the travel of the movable
venturi section. The fuel slots are tapered in the fuel bar such
that the fuel metering area is proportional to the venturi throat
area.
The air velocity at the venturi throat is sonic for all inlet
manifold vacuum pressures** in excess of approximately five inches
of mercury.
The variable area entrance to the venturi is designed such that the
velocity at any point in the entrance is a fixed percentage of the
velocity at the venturi throat. The fuel bar is located a fixed
distance upstream of the venturi throat to give ample velocity over
the fuel bar to provide good distribution and small fuel particle
size. Further reduction in fuel particle size occurs as the mixture
of air and fuel passes through the shock waves associated with
supersonic and subsonic velocities as they occur in the diffuser
section of the venturi.
* and in schematic form in Figure 1
** depressions
-------
The total pressure differential that is available for fuel metering
is the differential from the float bowl to the venturi vacuum at
the fuel bar. An airflow bleed network is used with both fixed and
variable restrictions to use the correct percentage of this avail-
able pressure differential for fuel metering.
Cold enrichment is achieved through the use of a carburetor electric
choke mechanism to control the fuel metering pressure differential
as a percentage of the total available pressure differential. This
cold enrichment fuel/air ratio is thus metered as a function of
engine compartment temperature (sensed in the air cleaner, after
the filter) and time from engine start.
The cold crank fuel is supplied when the engine is cold during
crank cycle only. Also, to avoid fuel flooding, the crank fuel can
be shut off during the cold crank by selecting wide-open throttle
position.
A conventional carburetor acceleration fuel pump delivers fuel in
proportion to a change in throttle position. This fuel is injected
into the airstream ahead of the fuel bar.
Power enrichment is achieved by sensing manifold vacuum and increasing
the fuel/air ratio for low manifold vacuum. This is accomplished
by increasing the fuel metering pressure differential from the
normal part throttle metering level as a function of manifold
vacuum. Power enrichment also occurs near wide-open throttle by
the contour on the fuel bar."
Test Program
Exhaust emissions and fuel economy tests were conducted in accordance
with the 1975 Federal Test Procedure ('75 FTP), the EPA Highway Fuel
Economy Test (HFET), and steady state tests. Evaporative emissions were
not measured.
Numerous tests were conducted with various emission control systems and
air/fuel ratios. The basic mixture is adjusted with a trim setting
screw, such that turning out (opening) the trim setting screw increases
the air/fuel ratio. The mixtures tested are referred to in terms of the
number of turns open (T.O.) of the trim setting screw. The air/fuel
ratios corresponding to the various trim settings are shown in Figure 3.
For tests run with the secondary air disconnected, the output hose from
the air pump was disconnected at the pump, and the hose was plugged.
For all '75 FTP's with EGR, the activation of the EGR was delayed until
70 seconds after the start of the test.
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Figure 1 - Sonic Carburetor Schematic
Air into
Carburetor
Top View
1 Fuel metering bar
2 Venturi throat
3 Movable venturi section
Throttle control rod
Section A-A
*in
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AIR
TEA/P
TIME
INC. TEMP
TIME
F I G U R E 2
COLO ENRICHMENT
MANIFOLD
VACUUM
VACUUM
POWER ENRICHMENT
THROTTLED
THROTTLE
BASIC SCHEDULE
Sf
FUNCTIONAL
BLOCK DIAGRAM
SONIC CARBURETOR
MODEL 1985
COlttnJuStrfSS
Hollay Carburetor
Division
11155 Eul N1M UiM (toad
P. O Bos 749
Wui.n. UicNgut 4MMO
A division of tM Con inoultflta
&THROTTLE
ACCELERATOR PUMP
CRANK
SIGNAL
ENGINE
TEMP
CRANK
RUN
TEMP
CRANK FUEL
AIRFLOW
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Figure 3
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The following tests were conducted:
I. Oxidation Catalyst Installed, with EGR
A. 5% Idle Enrichment, Secondary Air Disconnected
# of
Tests 2 3/4 Turns Open (T.O.)
7 '75 FTP (EGR after 70 sec.)
7 HFET
2 sets of Steady States
B. 0% Idle Enrichment
1. Secondary Air Connected
9 '75 FTP @ 0-2 T.O. (EGR after 70 sec.)
4 HFET @ 0-2 T.O.
4 sets of Steady States @ 0-2 1/4 T.O.
2. Secondary Air Disconnected
4 '75 FTP @ 0-3 T.O. (EGR after 70 sec.)
1 HFET @ 3 T.O.
1 set of Steady States @ 3 T.O.
II. Three-Way Catalyst Installed, Sec. Air Disconnected, 0% Idle Enrichment
A. With EGR
14 '75 FTP (EGR after 70 sec.) @ 0-3 1/2 T.O.
4 HFET @ 1 T.O.
1 set of Steady States @ 35 mph, 0-1/2 T.O.
1 set of Steady States @ 1 T.O.
B. Without EGR
1 '75 FTP @ 1 T.O.
4 Hot Start LA-4 @ 1 1/2-3 T.O.
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Test Results - Emissions
The results of the '75 FTP testing with the oxidation catalyst installed
are shown in Figure 4 and Table 1. For air/fuel trim adjustments leaner
than 1/2 turn open the emission levels are within the 1977 federal
standards while yielding city fuel economies of 15-16 liters/100 km (15-
16 mpg).
The effect of disconnecting the secondary air at very lean mixtures is a
slight increase in HC and CO emissions coupled with a similar decrease
in NOx. The data for the test with the air/fuel trim adjustment zero
turns open with the secondary air disconnected is not included in Figure
4 due to its extremely high CO value. This indicates that secondary air
is essential to clean operation in the richer ranges tested.
When the oxidation catalyst was replaced with a 3-way catalyst, a series
of tests at 35 mph was run with the modal analyzer. The results are
shown in Figure 5 and Table 2. The significant aspect of these results
is the narrow "window" of air/fuel ratios (near 1/3 turn open) for which
the 3-way catalyst is effective.
The next series of '75 FTPs was run at trim settings somewhat leaner
than 1/3 turn open in an attempt to compensate for the enrichment supplied
during the acceleration portions of the test cycle. Figure 6 and Table
3 show that relative to the oxidation catalyst the 3-way catalyst substantially
reduced NOx emissions, while HC emissions increased slightly, and CO
emissions increased drastically to over 20 g/mi (12 g/km). The fact
that the emission control capability demonstrated in the steady state
testing (Tables 2, 4, 5) was not reflected in the FTP data indicates
that the air/fuel ratio was not held stable during the numerous tran-
sients of the FTP.
To get a better idea of what was occurring, the FTP emissions were
analyzed by mode for acceleration, cruise, and deceleration. Figures 7
through 11 show that the major problem areas for both HC and CO were the
acceleration portions of the test cycle. This can be attributed to the
enrichment of the mixture by the accelerator pump and power enrichment
system to a point outside the effective operating "window" of the 3-way
catalyst. This meant that an even leaner range needed investigation.
To investigate emissions in a leaner mixture range a series of hot start
LA-4's was conducted without EGR at air/fuel trim adjustments ranging
from 1.5 to 3 turns open. Although the hot LA-4 emissions results
cannot be compared directly to the '75 FTP emissions, both procedures
would show similar trends. Figure 12 shows that there is no significant
variation of emissions in the trim adjustment range of 1.5 to 3 turns
open. The lack of EGR in these tests resulted in relatively high NOx
emission levels with low HC and CO levels. Therefore, '75 FTP's were
conducted with EGR at trim adjustments of 2 1/2 and 3 1/2 turns open.
This configuration reduced NOx emission substantially, but CO emissions
returned to over 15 g/mi (9.3 g/km).
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10
During the '75 FTP, emission samples are collected in three bags - cold
transient, cold stabilized, and hot transient. Emissions during the
cold transient phase (bag 1) are affected by warm-up time of the catalyst
and operation of the carburetor cold enrichment system. The percentage
of composite '75 FTP emissions contributed by bag 1 (see Table 8) indi-
cates the effect of these factors on emissions. With the oxidation
catalyst a large percentage of total HC and CO emissions comes from bag
1, but with the three-way catalyst these percentages are much smaller.
It should be noted that the actual bag 1 mass emissions depend on the
total composite emissions as well as the bag 1 percentages.
Fuel Economy
Results for the highway fuel economy tests appear in Table 6. The
results ranged from 22.1 mpg to 25.4 mpg, where the highest values were
achieved with the 3-way catalyst. This is slightly below the 26.0 mpg
that the baseline vehicle averaged after 4000 miles durability accumulation.
Driveability
No quantitative driveability tests were conducted, but the following
observations were noted:
(1) All cold starts-(all '75 FTPs) required at least three pumps of the
accelerator pedal.
(2) All cold starts were accompanied by at least one backfire through
the carburetor and usually a stall.
(3) Drivers considered the vehicle seriously underpowered. Acceleration
times for 0-60 mph ranged from twenty to twenty-five seconds.
Comparison With Baseline
The sonic carburetor operating in conjunction with other emission control
devices was able to maintain emissions within the 1977 Federal Standards.
However, this test program was conducted to evaluate the relative merits
of the sonic carburetor versus the production carburetor. Test results
supplied by Holley for the baseline vehicle with production carburetor
(Holley model 1945) appear in Table 7.
Hydrocarbon emissions of the test vehicle remained comparable to the
production vehicle. The minimum average CO value for a given test
vehicle configuration was over 5 g/mi (3 g/km) compared to 2.3 g/mi (1.5
g/km) for the production vehicle. Excluding tests with CO levels above
current standards, minimum NOx emission levels were approximately 1.1
g/mi (0.7 g/km) compared to 0.9 g/mi (0.6 g/km) for the production
vehicle. The test calibration which yielded the best highway fuel
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11
economy while meeting the 1977 federal emission standards consisted of
setting the air/fuel trim adjustment two turns open and using the oxidation
catalyst. This maximum fuel economy was 24.1 mi/gal (9.8 L/100 km),
which is slightly less than the 26.0 mi/gal (9.0 L/100 km) of the pro-
duction vehicle. Driveability of the test vehicle was poor, but that of
the same vehicle in baseline condition was also poor.
In summary, there were no configurations tested for which the sonic
carbureted vehicle was able to achieve emissions and fuel economy results
comparable to the production vehicle.
Applicability of Results
The conclusions drawn from this EPA evaluation test are valid only for
the specific test vehicle used. A complete evaluation of the effective-
ness of any system in achieving improvements on various types of vehicles
requires a much larger sample of test vehicles than is feasible in the
evaluation projects conducted by EPA. Test results for one vehicle
serve only as an indication of results likely to be obtained in the
testing of another vehicle of similar specification.
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Table 1
'75 FTP Mass Emissions
Oxidation Catalyst with EGR Activated After 70 Seconds
Test
Number
2 3/4 T.O., 5%
77-5349
78-0331
78-0350
78-0384
78-0446
78-0469
78-0483
Average
0 T.O. 0% Idle
78-0548
78-1418
Average
1/2 T.O.
78-1288
78-1321
78-1416
Average
1 T.O.
78-0775
78-1420
Average
2 T.O.
78-0845
78-1548
Average
0 T.O. No Sec.
78-0526
2 1/4 T.O.
78-0447
3 T.O.
78-1025
78-1582
Average
HC
g/km
Idle Enrich,
. 45 •
.32
.32
.35
.25
.30
.32
.33
Enrich, with
.37
.39
.38
.31
.30
.30
.30
.27
.35
.31
.35
.26
.31
Air
1.53
.37
.42
.42
.42
CO
(g/mi) g/km
No Secondary Air
(.73) 4.98
(.51) 2.64
(.52) 3.98
(.56) 4.59
(.41) 3.27
(.49) 3.10
(.52) 3.51
(.53) 3.72
Sec. Air
(.60) 14.79
(.63) 13.34
(.62) 14.07
(.50) 6.18
(.49) 3.95
(.49) 3.70
(.49) 4.61
(.44) 4.54
(.56) 2.01
(.50) 3.28
(.57) 2.39
(.42) 4.51
(.50) 3.45
(2.46) 56.25
(.59) 3.98
(.67) 1.95
(.68) 8.23
(.68) 5.09
(g/mi)
(8.01)
(4.24)
(6.41)
(7.39)
(5.26)
(4.98)
(5.65)
(5.99)
(23.80)
(21.47)
(22.64)
(9.95)
(6.36)
(5.95)
(7.42)
(7.31)
(3.23)
(5.27)
(3.85)
(7.25)
(5.55)
(90.5)
(6.40)
(3.13)
(13.25)
(8.19)
CO 9
NOx
(g/mi)
362
337
356
356
342
343
336
347
360
373
367
336
364
361
354
342
360
351
339
354
347
272
336
357
352
355
(580)
(600)
(590)
(541)
(585)
(581)
(569)
(550)
(579)
(565)
(545)
(570)
(558)
(438)
(541)
(574)
(567)
(571)
g/km
.84
.63
.83
.92
.71
.73
.80
.78
.40
.38
.39
.78
.75
.72
.75
.88
.83
.85
.90
.85
.88
(g/mi)
(1.35)
(1.02)
(1.33)
(1.48)
(1.15)
(1.17)
(1.29)
(1.26)
(0.65)
(0.61)
(0.63)
(1.25)
(1.20)
(1.16)
(1.20)
(1.41)
(1.33)
(1.37)
(1.45)
(1.37)
(1.41)
.35
.72
.60
.73
.67
(0.57)
(1.16)
(0.97)
(1.18)
(1.08)
Fuel Consumption
litres/100 km (miles/gal)
15.8
14.6
15.5
15.6
14.9
14.9
14.6
15.1
16.4
16.8
16.6
14.8
15.8
15.7
15.4
14.9
15.6
15.2
14.7
15.5
15.1
15.6
14.7
15.4
15.7
15.5
(14.9)
(16.1)
(15.2)
(15.1)
(15.8)
(15.8)
(16.1)
(15.6)
(14.3)
(14.0)
(14.2)
(15.9)
(14.9)
(15.0)
(15.3)
(15.8)
(15.1)
(15.5)
(16.0)
(15.2)
(15.6)
(15.1)
(16.0)
(15.3)
(15.0)
(15.2)
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35 mph
0 T.O.
1/4 T.O.
3/8 T.O.
1/2 T.O.
1 Turn Open
Speed Test //
78-1696
78-1697
HC (ppm)
HC
g/km
.96
.02
.11
.02
.02
1688
1200
50
73
(g/mi)
(.96)
(.03)
(.17)
(.03)
(.03)
Table 2
Steady State Emissions
3-way Catalyst with EGR
0% Idle Enirchment No Secondary Air
CO (ppm)
CO
g/km
2.52
.01
.48
0.0
0.0
1.
0.
0.
0.
(g/mi)
(2.52)
(0.02)
(0.77)
(0.0)
(0.0)
49
45
0
0
g/km
5734
234
168
173
222
CO 2
(g/mi)
(5734)
(376)
(271)
(278)
(357)
C02 (ppm)
12.78
13.35
13.60
13.50
NOx
g/km (g/mi)
6.72
.24
.01
.44
1.46
(6.72)
(0.38)
(.02)
(.71)
(2.35)
NOx (ppm)
4.66
3.50
90.0
150.0
Fuel Consumption
litres/100 km (miles/gal)
2.46
10.0
7.2
7.4
9.4
(.65)
(23.6)
(32.5)
(31.9)
(24.9)
* grams/hour, liters/hour (gal/hour)
-------
NO EGR
1 78-3820
Table 3
'75 FTP Mass Emissions
3-Way Catalyst with EGR Activated After 70 Seconds, No Secondary Air
(.43)
(M) Modal analyzer test data
* Small exhaust leak
CO
CO 2
NOx
g/km (g/mi)
Fuel Consumption
litres/100 km (miles/gal)
98
57
80
64
45
66
55
58
68
57
48
46
(1.58)
(.92)
(1.29)
(1.03)
(.72)
(1.07)
(.89)
(.94)
(1.09)
(.91)
(.77)
(-74)
29.37
18.35
24.21
17.57
13.16
18.99
17.49)
17.88
16.43
16.62
10.29
12.22
(47.25)
(31.13)
(38.95)
(28.27)
(21.17)
(30.55)
(28.14)
(28.77)
(26.43)
(26.74)
(16.55)
(19.67)
326
331
339
331
321
334
336
329
331
327
363
362
(524)
(533)
(546)
(532)
(516)
(538)
(541)
(529)
(532)
(526)
(584)
(583)
.05
.14
.08
.11
.17
.12
.14
.13
.16
.16
.32
.31
(.08)
(.22)
(.13)
(.18)
(.28)
(.19)
(.23)
(.21)
(.25)
(.25)
(.52)
(.50)
14
14
15
15
16
16
.4
.4
.3
.3
.2
.3
(16
(16
(15
(15
(14
(14
.3)
.3)
.4)
.4)
.5)
.4)
(9.87)
(535)
(3.25)
(16.1)
to
u>
Test
HC
1 1/2 78-3819
2 78-3818
2 1/2 78-3817
3 78-3816
.05
.06
.06
.06
Hot Start LA-4 Mass Emissions
3-Way Catalyst, No EGR, No Secondary Air
CO
CO 2
NOx
.05
.06
.06
.06
(.08)
(.10)
(.10)
(.10)
.53
.60
.52
.48
(.85)
(.97)
(.84)
(.77)
324
322
321
318
(521)
(518)
(516)
(512)
2.18
2.16
2.18
2.22
(3.50)
(3.48)
(3.51)
(3.57)
13.8
13.8
13.8
13.6
litres/100 km (miles/gal)
(17.0)
(17.1)
(17.1)
(17.3)
-------
Test
Number
2 3/4 T,
Idle*
10
20
30
40
50
60
Idle*
10
20
30
40
50
60
0 T.O. ,
Idle*
10
20
30
40
50
60
1 T.O.
Idle*
15
30
40
50
60
HC
g/km
(g/mi)
CO
g/km
(g/mi)
.0., 5% Idle Enrich, No Secondary Air
77-5354
77-5355
77-5356
78-0448
78-0449
78-0445
0% Idle
78-0549
_
78-0550
78-0551
78-0527
78-0528
1.8
.05
.06
.11
.07
.06
.04
.04
.06
.11
.07
.05
.03
Enrich,
.07
.03
.07
.06
.05
.04
.02
.12
.09
.07
.05
(1.8)
(.08)
(.09.)
(.17)
(.11)
(.09)
(.06)
(1.1)
(.07)
(.09)
(.18)
(.11)
(.08)
(.05)
With Sec.
(1.7)
(.11)
(.05)
(.12)
(.09)
(.08)
(.07)
(.24)
(.03)
(.19)
(.14)
(.11)
(.08)
22.2
.19
.06
.03
.02
.02
.04
0.00
0.00
.01
.01
.02
.02
.04
Air
2.9
.14
.09
.06
.07
.07
.19
0.00
0.00
.01
.01
.02
.03
(22.2)
(.31)
(.10)
(.05)
(.03)
(.04)
(.06)
(0.00)
(0.00)
(.01)
(.02)
(.03)
(.04)
(.07)
(2.9)
(.22)
(.15)
(.09)
(.12)
(.12)
(.30)
(0.00)
(0.00)
(.02)
(.02)
(.04)
(.05)
Table 4
Steady State Mass Emissions
Oxidation Catalyst with EGR
CO?
NOx
Fuel Consumption
g/km
5317
322
181
169
172
196
231
5237
319
224
180
175
186
246
6800
410
216
172
172
200
238
5668
233
173
182
197
224
(g/mi)
(5317)
(518)
(292)
(272)
(277)
(315)
(372)
(5237)
(514)
(360)
(290)
(282)
(300)
(396)
(6800)
(660)
(347)
(277)
(276)
(322)
(383)
(5668)
(375)
(278)
(293)
(317)
(360)
g/km
3.96
.18
.14
.11
.24
.37
.76
3.5
.17
.16
.12
.27
.38
.63
11.5
.62
.29
.21
.48
.88
1.87
7.32
.26
.14
.30
.52
1.35
(g/mi)
(3.96)
(.29)
(.22)
(.17)
(.39)
(.59)
(1.22)
(3.5)
(.28)
(.26)
(.20)
(.44)
(.61)
(1.01)
(11.5
(1.00)
(.47)
(.33)
(.77)
(1.41)
(3.01)
(7.32)
(.42)
(.22)
(.49)
(.84)
(2.17)
litres/100 km
2.28
13.8
7.7
7.2
7.3
8.3
9.9
2.24
13.6
9.6
7.7
7.5
7.9
10.5
2.91
17.6
9.2
7.4
7.3
8.5
10.2
2.42
9.9
7.4
7.8
8.4
9.5
(miles/gal)
(.603)
(17.1)
(30.4)
(32.6)
(32.0)
(28.2)
(23.8)
(0.591)
(17.3)
(24.6)
(30.5)
(31.4)
(29.6)
(22.4)
(0.769)
(13.4)
(25.5)
(32.0)
(32.1)
(27.6)
(23.1)
(0.64)
(23.7)
(31.9)
(30.2)
(27.9)
(24.7)
* grams/hour, liters/hour (gal/hour)
-------
Table 5
Steady State Mass Emissions
Oxidation Catalyst with EGR, 0% Idle Enrichment
Speed
2 T.O.
Idle*
15
30
40
50
60
2 1/4 T.O.
Idle*
10
20
30
40
50
60
3 T.O., No
Idle*
15
30
40
50
60
Test
Number
HC
g/km
(g/mi)
, With Secondary Air
78-0846
78-0847
78-0519
78-0520
78-0551
Secondary
78-1027
.90
.04
.16
.13
.07
.04
1.08
.05
.07
.10
.10
.05
.02
Air
1.00
.03
.14
.10
.05
.02
(.90)
(.07)
(.26)
(.21)
(.12)
(.06)
(1.08)
(.08)
(.11)
(.16)
(.16)
(.08)
(.04)
(1.00)
(.05)
(.22)
(.16)
(.08)
(.04)
CO
CO?
NOx
g/km (g/mi)
Fuel Consumption
litres/100 km (miles/gal)
90
04
16
13
07
04
(.90)
(.07)
(.26)
(.21)
(.12)
(.06)
0.00
0.00
.02
.04
.04
.05
(0.00)
(0.00)
(.04)
(.06)
(.06)
(.08)
5243
245
183
184
207
229
(5243)
(395)
(295)
(296)
(333)
X368)
4.60
.21
.11
.19
.34
.72
(4.60)
(.33)
(.17)
(.31)
(.55)
(1.16)
2.23
10.5
7.8
7.9
8.8
9.8
(.59)
(22.5)
(30.0)
(29.9)
(26.6)
(24.1)
.08
.05
.07
.10
.10
.05
.02
(1.08)
(.08)
(.11)
(.16)
(.16)
(.08)
(.04)
0.00
0.00
0.00
.02
.02
.03
.04
(0.00)
(0.00)
(0.00)
(.03)
(.04)
(.05)
(.06)
4540
311
173
165
185
186
234
(4540)
(501)
(278)
(265)
(297)
(299)
(376)
3.16
.16
.14
.09
.19
.30
.62
(3.16)
(.26)
(.23)
(.15)
(.31)
(.49)
(.99)
1.94
13.3
7.4
7.0
7.9
7.9
(0.513)
(17.7)
(31.9)
(33.4)
(29.9)
(29.6)
(23.6)
5179
226
177
182
206
233
(5179)
(364)
(285)
(293)
(332)
(375)
N5
Ul
*grams/hour, liters/hour (gal/hr)
-------
Table 6
Highway Fuel Economy Test
With EGR
Test
Number
2 3/4 T
77-5351
77-5352
77-5353
77-5411
78-0386
78-0388
78-0470
Average
0 T.O. ,
78-1417
78-1419
Average
1 T.O.
78-1421
2 T.O.
78-1322
3 T.O.
78-1583
1 T.O.
78-1691
78-1694
78-1695
78-1698
Average
g/km
HC
(g/mi)
.0. Oxidation Catalyst, 5%
.11
.03
.06
.04
.09
.07
.06
.06
0% Idle Enrich,
.06
.06
.06
.06
.05
.06
3-way Catalyst,
.12
.12
.10
.10
.11
(.18)
(.05)
(.10)
(.06)
(.14)
(.11)
(.09)
(.10)
With Sec.
(.09)
(.10)
(.10)
(.09)
(.08)
(.10)
CO
g/km
(g/mi)
CO 2
g/km
(g/mi)
Idle Enrich, No Secondary Air
.08
.14
.39
.17
.17
.45
.04
.21
Air
.24
1.47
.86
.07
.16
.54
(.13)
(.23)
(.62)
(.28)
(.27)
(.72)
(.07)
(.33)
(.39)
(2.36)
(1.38)
(.11)
(.25)
(.87)
273
244
245
249
245
232
239
247
236
237
236
234
229
239
(440)
(393)
(395)
(401)
(395)
(373)
(385)
(397)
(379)
(381)
(380)
(376)
(368)
(384)
No Sec. Air.
(.20)
(.19)
(-16)
(-16)
(.18)
3.90
2.69
2.18
2.81
2.90
(6.27)
(4.33)
(3.51)
(4.52)
(4.66)
215
223
213
217
217
(346)
(359)
(343)
(349)
(349)
NOx
g/km
.56
.44
.58
.62
.66
.60
.60
.58
.98
.76
.87
(g/mi)
(.90)
(.71)
(.94)
(1.00)
(1.06)
(.96)
(.96)
(.93)
(1.57)
(1.22)
(1.40)
Fuel Consumption
liters/100 km (miles/gal)
.90 (1.45)
,90
.38
.52
.50
.52
.48
(1.45)
,75 (1.20)
(.61)
(.84)
(.81)
(.83)
(.77)
11
10
10
10
10
9.9
10.2
10.5
10.1
10.2
10.1
10.0
9.8
10.2
9.4
9.7
9.3
9.4
9.4
(20.1)
(22.5)
(22.4)
(22.1)
(22.4)
(23.7)
(23.0)
(22.3)
"(23.4)
(23.0)
(23.2)
(23.6)
(24.1)
(23.0)
(24.9)
(24.2)
(25.4)
(24.9)
(24.9)
NJ
ON
-------
Table 7
Baseline Data
Holley Tests of Production Vehicle After 4000 Mile AMA Durability
'75 FTP
HC
CO
NOx
g/km (g/mi)
.20
.22
.43
.30
.28
Average:
.29
(.33)
(.36)
(.70)
(.48)
(.45)
(.46)
g/km
1.4
1.7
1.3
1.3
1.6
(g/mi)
(2.3)
(2.6)
(2.0)
(2.1)
(2.5)
1.5
(2.3)
g/km
0.6
0.6
0.6
0.6
0.6
0.6
(g/mi)
(0.9)
(0.9)
(1.0)
(0.9)
(1.0)
(0.9)
Fuel Consumption
liters/100 km (miles/gal)
13.6
12.4
13.0
12.7
12.6
12.9
(17.3)
(18.9)
(18.1)
(18.5)
X18.7)
(18.3)
9.2
9.1
8.9
9.0
HFET
(25.6)
(25.9)
(26.4)
(26.0)
NJ
-------
28
Table 8
Percent Contribution to '75 FTP Composite Emissions
(Cold Transient)
Oxidation Catalyst
Trim Adjust
(Turns Open)
2 3/4*
0
1/2
1
2
0
2 1/4
3
Three-Way Catalyst
1/2
5/8
3/4
7/8
1
1 1/8
2 1/2
3 1/2
Secondary
Air
No
Yes
Yes
Yes
Yes
No
No
No
No
No
No
No
No
No
No
No
HC_ C0_ NOx
68 74 27
48 48 29
61 65 33
70 62 31
75 85 28
31 28 28
77 77 30
70 62 33
31 34 71
39 43 28
37 38 44
34 34 37
44 36 42
36 41 34
58 46 32
54 50 32
-------
Table 9 p. 29
TEST VEHICLE DESCRIPTION
Chassis model year/make - 1975 Dodge Dart
Emission control system - Sonic Carburetor, Catalyst, Air Injection,
EGR
Engine
type 4 stroke, Otto cycle, 1-6, ohv
bore x stroke 3.41 in. x 4.12 in. (87 mm x 105 mm)
displacement 225 cu in. (3687 cc)
compression ratio 8.4:1
maximum power @ rpm 100 hp @ 3600 (75 kW)
fuel metering Holley sonic carburetor - model 1985 (base-
fuel requirement line, Hoiley 1 bbl carb - model 1945)
unleaded; tested with Indolene HO, unleaded,
Drive Train with 0.03 wt;% sulfur
transmission type 3 speed automatic
final drive ratio 3.23
Chassis
type front engine, rear wheel drive
tire size D78-14
curb weight -. . . . 3100 Ib (1405 Kg)
inertia weight 3500 Ib (1587 Kg)
passenger capacity 5
Emission Control System
basic type oxidation catalyst, air injection, back
pressure modulated EGR
additional features . sonic carburetor; also tested with 3-way
catalyst.
------- |