75-9 DWP
Evaluation of a Turbocharged
TCCS Powered Plymouth Cricket
October 1974
Technology Assessment and Evaluation Branch
Emission Control Technology Division
Office of Air and Waste Management
Environmental Protection Agency
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Background
The Environmental Protection Agency receives information about
many systems which appear to offer potential for emission reduction or
fuel economy improvement compared to conventional engines and vehicles.
EPA's Emission Control Technology Division is interested in evaluating
all such systems, because of the obvious benefits to the Nation from
the identification of systems that can reduce emissions, improve
economy, or both. EPA invites developers of such systems to provide
to the EPA complete technical data on the systems principle of opera-
tion, together with available test data on the system,. In those
cases in which review by EPA technical staff suggests that the data
available show promise, attempts are made to schedule tests at the
EPA Emissions Laboratory at Ann Arbor, Michigan, The results of all
such test projects are set forth in a series of Technology Assessment
and Evaluation Reports, of which this report is one.
The conclusions drawn from the EPA evaluation tests are necessarily
of limited applicability. A complete evaluation of the effectiveness
of an emission control system in achieving performance improvements
on the many different types of vehicles that are in actual use requires
a much larger sample of test vehicles than is economically feasible
in the evaluation test projects conducted by EPA» For promising
systems it is necessary that more extensive test programs be carried
out. - ' . .
The conclusions from the EPA evaluation tests can be considered
to be quantitatively valid only for the specific test car used,
however, it is reasonable to extropolate the results from the EPA
test to other types of vehicles in a directional or qualitative manner,
i.e., to suggest that similar results are likely to be achieved on
other types of vehicles.
As part of the EPA stratified charge evaluation program, the
Emission Control Technology Division of the Office of Mobile Source
Air Pollution Control contacted Texaco, Incorporated concerning
the loan of a test vehicle powered by a Texaco Controlled Combustion
System (TCCS) engine. A vehicle was supplied courtesy of Texaco and
a test program was conducted by the Technology Assessment and Evalua-
tion Branch.
Vehicle Description
The vehicle tested was a catalyst-equipped 1972 Plymouth Cricket,
with a turbocharged 4-cylinder 141 cubic inch, TCCS engine and 3-speed
automatic transmission. The car is described in detail in the Vehicle
Description table on the following page and the TCCS concept is described
in the text following this table.
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TEST VEHICLE DESCRIPTION
Chassis model year/make - Cricket *72/Plymouth
Emission control system - Stratified charge engine with catalyst
Engine
type .... turbocharged/4 cycle/4 cylinder/ liquid cooled/
stratified charge
bore x stroke. ........ .3.875" x 3.000" (98.2mm x 76.2mm)
displacement 141 in3 (2300cc)
compression ratio 10:1
maximum power @ rpm 80 hp (107 Kw) @ 4000 rpm
fuel metering Roosa Master Diesel injection (pump and
injectors)
fuel requirements . . multi-fuel (limited by injection pump
capabilities)
Drive Train
transmisstion unitized construction front
engine, rear wheel drive
final drive ratio. . . 3.23
Chassis
tire size 155 SR 13 radial
curb weight 2200 Ibs. (1000 Kg)
inertia weight . 2500 Ibs. (1140 Kg)
passenger capacity 4
Emission Control System
basic type ...... Catalyst
oxidation catalyst location. . .immediately down stream of turbo & @ normal
rear silencer
substrate. gam ma alumina on inconel mesh
volume ............1.6 litres after turbo
2.0 litres @ rear silencer
loading. . 0.07 oz. platinum after turbo
0.12 oz. platinum at rear silencer
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The TCCS engine concept has multifuel capabilities. A Diesel
type direct cylinder injection system and a long duration constant
potential ignition system is incorporated in the TCCS engine. Figure 1
illustrates the basic arrangement of components. The process works
in the following manner. During the intake stroke a swirl is in-
parted to the fresh air charge. This is accomplished by tangential
intake port to cylinder geometry and a masked or shrouded intake
valve (see Figure 1). During compression the swirl rate is increased
due to conservation of momentum as the already swirling air is forced
into the smaller (than cylinder bore) piston cup. Injection and
ignition commence approximately 15 to 25 degrees before top dead
center. Fuel is injected into the swirling air and at the same time
the ignition begins sparking. The ignition plug continues sparking
while the injected fuel is mixed with air and carried to the plug
by the swirl. At the plug ignition of the mixture is initiated
and during the process burning mixture is swirled away as fresh mixture
is continually brought to the ignition source. While injection is
occurring the combustion is proceeding in a manner similar to that of
a continuous, external combustion burner. When the injection is
complete the spark is shut off and the remainder of the expansion and
exhaust process occurs as in a conventional gasoline engine.
Since the fuel is burned almost at the same time it enters the
combustion chamber the fuel/air residence time is very short and no
"end gas" mixture is formed thus the engine has no octane requirement.
Since ignition is via spark the engine has no^ cetane requirement.
This insensitivity to octane and cetane is typical of external,
continuous combustion systems such as used in turbines or steam
engines but unique as far as internal combustion engines are concerned.
Unlike conventional gasoline engines, the TCCS engine does not
require intake air throttling to maintain good combustion. The air/
fuel mixture is always in the ignitable range at the spark plug
location despite the overall lean mixture of 100:1 that can be
realized during part load operation. The ability to run extremely
lean "overall" is a feature of most stratified charge concepts and
the Diesel engine. Unlike the conventional gasoline engine stratified
charge and Diesel engines depend on "local" rather than "overall"
mixture ratios for good combustion. The advantage of the ability
to run without throttling is that the losses associated with drawing
the fresh air charge into the cylinder (pumping losses) are lessened.
This can result in improved economy over the conventional gasoline
engine at partial loads. A historical problem with unthrottled
operation of open chamber stratified charge engines like the TCCS,
however, has been high hydrocarbon emissions. Throttling can be
applied to the engine to raise exhaust temperatures and reduce HC
emissions but when this is done, economy suffers.
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Exhaust gas recirculation (EGR) had previously been demonstrated
as a highly effective NOx reduction technique which can be applied
to stratified charge engines like the TCCS. The test vehicle,
however, was not equipped with EGR as this particular vehicle was
set up for optimum fuel economy with lesser attention to low NOx
emissions.
Test Procedure
Exhaust emissions tests were conducted according to the 1975
Federal Test Procedure ('75 FTP) described in the Federal Register
on November 15, 1972„ In addition several EPA Highway Cycles were
ran on this vehicle. All testing was conducted at 2500 Ibs. inertia.
During testing three fuels were used. These included indolene
unleaded gasoline, number 2 Diesel fuel, and a wide boiling range
distillate fuel supplied by Texaco. The wide boiling range fuel
supplied by Texaco was blended from available fuel stocks and re-
presents a theoretical high refinery yield fuel which has no octane
or cetane specification. Table 1 contains Texaco's test information
on this fuel.
For both the Diesel fuel and the wide boiling range fuel vehicle
testing a continuous analysis, heated flame ionization detector (FID)
technique similar to that used for light duty Diesel testing was
used to eliminate condensation losses which can occur when bag
samples and "cold" FIDs are used to measure exhaust from vehicles
fueled by fuels containing higher molecular weight hydrocarbons.
Test Results
'75 FTP gaseous emission test results are given in the attached
tables 2, 2a, 3, 3a, 4 and 4a for the three fuels. For the Diesel
fuel and wide boiling range fuel testing,hydrocarbon emission results
have been omitted for the cases where heated flame ionization measure-
ment was not usedi As noted in these tables the vehicle was tested
in two different configurations. After the initial testing Texaco
requested that the vehicle be returned to them for an in-house
demonstration project. Scuffed cylinders were discovered during
a check-up on arrival at Texaco. The scuffing may be partly a result
of low engine oil pressure as observed when the vehicle was delivered
to EPA. Texaco rebuilt the engine and added an intake air throttle
to achieve better hydrocarbon control during the remaining EPA
tests. The throttle was set up such that throttling is only achieved
at idle and deceleration.
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SCHEMA! I C,TCCS
INTAKE
VALVE
INTAKE PORT
SPARK
PLUG
PISTON
FIGURE 1
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The data in the attached tables of results illustrate that while
emission levels, better than 1975 interim standards can be achieved,
high hydrocarbon emissions prevented achievement of the 1977 levels
of .41 gpm HC, 3.4 gpm CO and 2.0 gpm NOx. It appears that the engine
rebuild and throttling had little influence on emissions but it did
cause a 10 to 15% loss in fuel economy as illustrated in table 4. This
would be expected due to the increase pumping loss which occurs during
throttled conditions. .
Fuel economy comparison of the initial gasoline testing of this
TCCS vehicle with the '75 FTP sales-weighed, results from the 1975 certifica-
tion car fleet shows 35% better fuel economy (see table 4 for the TCCS
Cricket). The TCCS vehicle run on Diesel fuel gets about equivalent
economy to a Peugeot 204 Diesel passenger car of the same test inertia
(see table 2). '
Highway cycle results are given in table 5 and 5a. All highway
cycle testing was conducted after the engine rebuild. No gasoline fuel
data is available for the TCCS vehicle tested over the highway cycle.
Comparison with a Peugeot 204 Diesel of similar weight shows that this
TCCS vehicle gets slightly better fuel economy.
Aldehyde levels as measured by the EPA MBTH method are given in
table 6. In comparison with other late model cars this TCCS vehicle
appears to yield low aldehyde emissions. When compared with a Peugeot
504 Diesel aldehydes appear equivalent.
Conclusion
A turbocharged catalyst equipped TCCS powered Plymouth Cricket
demonstrated the ability to meet 1975 interim levels on three different
fuels with high fuel economy. Durability of the catalyst, however,
was not determined.
Compliance with the 1977 and later HC standard of .41 gpm will
require additional control devices or basic combustion improvement beyond
that demonstrated in this test.
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Table 1
Wide Boiling Range Fuel
Stock Vol %
Hvy. St. Run 13
Lt. St. Run 12
FCC 25
Diesel Fuel 25
Avjet 25
Identification . . 214-38
Gravity, API ......... 46.1
Sulfur, % (LAMP) ....... .0.16
TEB, ml/gal. .„.......< 0.05
RVP, Ibs 3.3
Distillation, ASTM, °F
IBP. 121
20% 225
50%. i 379
90%. . . . 532
Octane number
ASTM-R (RON) . 60
ASTM-M (MON) 48
Cetane Number. ........ 34.8-
% Hydrogen ........... 13.7
% Carbon ........'... 86.3
Gross Heating Value. .... .19535 BTU/lb.
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Table 2
Diesel Fuel Results
Test No.
15-55*
15-41*
15-43*
Avg. wo/throttling
16-4994
16-5046
Avg. w/ throttling
'75 FTP
HC
g/mi
0.89
N/A
N/A
.89
1.01
Oo98
1.00
Results
CO
g/mi
0.95
2.30
2.40
1.88
0.78
1.16
.97
NOx
g/mi
1.79
1.94
1,99
1.91
1.76
1.88
1.82
Fuel Economy
MPG
30.4
31.2
30.7
30.8
28.9
27.9
28.4
* Early testing before engine rebuild and without idle/
deceleration throttle
Peugeot 204 Diesel '75 FTP @ 2500 Ibs; 28.3 mpg
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Table 2a
Diesel Fuel Results
Test No.
15-55*
15-41*
15.43*
Avg. wo/throttling
16-4994
16-5046
Avg. w/ throttling
'75 FTP
HC
g/km
0.55
N/A
N/A
0.63
0,61
Results
CO
g/km
0.59
1.43
1.49
0.48
0.72
NOx
g/km
. 1.11
1.21
1.24
1.09
1.17
Fuel Consumption
1/100 km
7.7
7.5
7.7
7.7
8.1
8.4
8.3
* Early testing before engine rebuild and without idle/
deceleration throttle
Peugeot 204 Diesel '75 FTP @ 2500 Ibs; 8.31 1/100 km
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Table 3
Wide Boiling Range
Fuel Results
Test No.
15-24*
15-27*
15-34*
Avg. wo/ throttling
15-5063
15-5064
Avg. w/ throttling
HC
g/mi
N/A
N/A
0.88
0.88
0.70
0.61
.66
CO
g/mi
1.10
0.75
1.05
0.97
0.82
0.74
.78
NOx
g/mi
1.47
Io59
1.78
1.61
1.78
1.94
1.86
Fuel Economy
MPG
28.8
30.4
29.8
29.7
25.3
24.8
25.1
* Early testing before engine rebuild and without idle/
deceleration throttle
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Table 3a
Wide Boiling Range
' Fuel Results
Testing No.
15-24*
15-27*
15-34*
Avg. wo/ throttling
15-5063
15-5064
Avg. w/throttling
HC
g/km
N/A
N/A
0»55
.55
Oo44
0.38
.41
CO
g/km
0.68
0.47
0.65
.60
0.51
0.45
o49
NOx
g/km
0.91
0.99
loll
1.00
1.11
1.21
1»16
Fuel Consumption
1/100 km
8.2
7-7
7.9
7.9
9.3
9.5
9.4
* Early testing before engine rebuild and without idle/
deceleration throttle
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Table 4
Gasoline Results
Testing No.
15-46*
15-49*
15-50*
Avg.
'75 FTP
HC
g/mi
1.48
1.42
1.21
1.37
Results
CO
g/mi
0.50
0.50
0.50
0.50
NOx
g/mi
1.87
1.79
1.87
1.84
Fuel Economy
MPG
27.4
29.6
28.3
28.4
* Early testing before engine rebuild and without idle/
deceleration throttle
Sales weighted fuel economy from '75 Cert, results for
2500 Ib. class is 21.2 mpg
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Table 4a
Gasoline Result:s
'75 FTP Results
Testing No.
15-46*
15-49*
15-50*
Avg.
HC
g/km
0.92
0.88
0.75
0.85
CO
g/km
0.31
0.31
0.31
0.31
NOx
g/km
1.16
1.11
1.16
1.14
Fuel Consumption
1/100 km
8.6
8.0
8.3
8.8
*. Early testing before engine, rebuild and without idle/
deceleration throttle
Sales weighted fuel consumption from '75 Cert, results for
2500 Ib. class is 11.1 1/100 km
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Table 5
Highway Cycle Results
Test No.
16-4994
15-5063
15-5064
Avg.
Fuel
Diesel
Wide Boiling Rg
Wide Boiling Rg
Wide Boiling Rg
flae/il -ina
HC
g/mi
0.43
0.33
N/A
0.33
CO
g/mi
0.37
0.37
0.31
0.34
NOx
g/mi
1.57
1.47
Io62
1.56
M/A ....
Fuel Economy
MPG
40.6
35.9
36.0
36.0
2500 Ib wt class Sales Weighted Highway Economy from '75
Cert =31.2 mpg
Peugeot 204 Diesel Highway Economy Tested at 2500 Ibs = 38,6 mpg
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Table 5a
Highway Cycle Results
test No.
16-4994
15-5063
15-5064
Avg.
Fuel
Diesel
Wide Boiling Rg
Wide Boiling Rg
Wide Boiling
HC
g/km
0.27
0.21
N/A
0.21
CO
g/km
0.23
0.23
0.19
0.21
NOx
g/kp
0.98
0.91
1.02
Oo97
-N/ A
Fuel Consumption
1/100 km
5.79
6.55
6.53
6.54
2500 Ib wt class Sales Weighted Highway Consumption
from '75 Cert = 7.5 1/100 Km
Peugeot 204 Diesel Highway Economy tested at 2500 Ibs =
6.1 1/100 Km
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Test No.
15-50
15-55
15-5063
15-5064
'73 Duster (225
CID Eng.)
Avg. 3 tests
'73 Maverick (302
CID Eng.)
Avg. 3 tests
Peugeot 504
Avg. 2 tests
Table 6
MBTH Aldehyde Results
Fuel
Gasoline
Diesel
Composite '75 FTP HC
gm/mi
ie 1.21
0.89
dling Rg. 0.70
dling Rg. 0.61
ALD'Y
g/mi
0.030
0.057
0.057
0.048
% ALD'Y
2.5
6.4
8.1
7.9
Diesel
1.80
2.25
0.84
0.116
0.104
0.048
6.5
4.6
5.7
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BAG 1
APPENDIX
Individual 1975 FTP Bag Results
BAG 2
BAG 3
Test No. Fuel
15-55* Diesel
15-41* "
15-43*
16^4994 "
16-5046 "
15-24* W.B.R.F.**
15-27* "
15-34*
15-5063
15-5064
15-46* Gasoline
15-49* "
15-50* "
HC CO C02 NOx Eco.
g/m g/m g/m g/m mpg
1.40 1.68 355.9 1.95 28.3
N/A 4.19 354.8 2.1-7 27.9
N/A 3.41 353.2 2.29 28.2
1.55 1.99 363.0 1.97 27.6
1.54 3.01 379.1 2.21 26.3
N/A 2.61 340.4 1.50 26.2
N/A 0.92 317.8 1.75 29.6
1.43 2.23 343.9 1.97 27.0
1.23 2.00 378.0 1.97 24.6
1.15 1.64 385.8 2.06 24.2
1.85 0.99 354.1 2.14 24.5
1.97 0.94 327.1 1.97 26.5
1.25 0.88 350.5 2.33 24.9
HC CO C02 NOx Eco.
g/m g/m g/m g/m mpg
0.70 0.44 331.6 1.65 30.7
N/A 1.73 316.0 1.82 31.8
N/A 2.21 320.8 1.79 31.3
0.87 0.28 359.5 1.62 28.2
0.89 0.47 365.1 1.68 27.7
N/A 0.59 332.1 1.37 28.3
N/A 0.65 306.7 1.44 30.6
0.99 0.60 310.8 1.61 30.6
0.58 0.36 385.7 1.67 24.5
0.41 0.36 389.1 1.79 24.2
1.37 0.26 312.5 1.67 28.0
1.40 0.32 288.1 1.61 30.3
1.41 0.29 299.9 1.58 29.1
HC CO C02 NOx Eco.
g/m g/m g/m g/m mpg
0.86 1.37 313.2 1.94 32.1
N/A 1.88 303.1 1.99 32.2
N/A 1.86 318.2 2.16 31.6
0.95 0.80 319.5 1.86 31.6
0.77 1.09 340.3 1.99 29.7
N/A 0.99 300.7 1.63 31.2
N/A 0.83 305.7 1.44 30.7
0.75 1.02 298.8 1.96 31.4
0.51 0.81 341.4 1.85 27.6
0.39 0.76 357.8 2.15 26.4
1.42 0162 303.3 2.05 28.7
1.01 0.54 281.2 2.02 31.1
0.81 0.53 293.5 2.07 29.9
* Early testing before engine rebuild and without idle/deceleration throttle
**
Wide boiling range fuel
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