71-1
Exhaust Emissions From Seven LP Gas Powered Vehicles
July 1970
H. Anthony Ashby
Division of Motor Vehicle Research and Development
National Air Pollution Control Administration
Department of Health, Education, and Welfare
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Subject: Evaluation of LP Gas powered automobiles
Seven LPG powered cars were delivered to building 2042 by
personnel of the St. Louis (Missouri) County Health Depart-
ment, and tested here on June 9 and 10, 1970. The cars
were all late model, standard sized American cars equipped
with V-8 engines and automatic transmissions. None had
air conditioning. All were equipped with Algas Industries
dual fuel carburetion systems.
The fleet consisted of;
Three 1969 Dodge Coronet 4 door wagons (318 C.I.D.)
Two 1969 Rambler Rebel 4 door station wagons (343 C.I.D.)
One 1969 Plymouth Satellite 4 door sedan (318 C.I.D.)
One 1968 Ford Ranch Wagon 4 door station wagon (302 C.I.D.)
Evaluation Procedure
Each car was tested according to the proposed 1972 Federal
procedure, which includes a cold start, the LA4-S3 driving
schedule, and emission sampling by the CVS method. Results
from these tests are presented for each car as mass emissions,
i.e., grams of pollutant per vehicle mile (gpm).
Following the 1972 test a hot-start two-cycle test was made
according to the 1970 Federal procedure, with the CVS method
being employed in addition to the continuous sampling. Data
from these two hot seven mode cycles are presented (1) as
concentrations and mass emissions as calculated by the 1^970
procedure, and (2) as mass emissions calculated from the* CVS
procedure. • . • ..
Results and Discussion
Results from the 1972 procedure tests are presented in Table
1, along with the average values for each make of car (Plym-
outh and Dodge being considered as one make). Note that re- ;
peat tests were made of Dodges 23 and 30 after mixture adjust-
ments were made by Mr. Ralph Abbott of Algas Industries.
Continuous hot cycle measurements indicate that idle CO was
in the range of 2 to 3 percent on these cars before adjustment,
and about .02 percent after. A third car, Rambler Rebel 29,
had a high CO mass from the 1972 test and an idle CO of about
2.7% on the hot California cycles. Idle CO on the other cars
ranged from 0.5% to 1.5%.
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-2-
Mass emissions- from 1972 procedure tests conducted at DMVPC
rece/itly using gasoline were picked at random from the files,
four' tests for each-vehicle type similiar to the St. Louis
County vehicles. The averages of these four tests are listed
in Table III according to car make. All Plymouth and Dodge
tests were of 318 C.I.D. engines, but it was not possible"
to find all Ford 302 and Rambler 343 data. However, all were
late model V-8's wi^th automatic transmission.
Comparison of Table I data with Table III data indicates the
chief advantage of LP Gas powered cars: good control of
carbon monoxide, with an average CO reduction of 71% being
shown in this comparison. Average HC reduction was 18.4% and
average NOx reduction was 28.6%.
Table II contains the results of the two hot .seven mode cycles,
calculated according.to the 1970 Federal procedure and presented
as concentrations and mass emissions. Simultaneous CVS mass
emissions for the last three tests are also presented.
For comparison with Table II concentrations some hot cycle
data from DMVPC certification and surveillance tests (using
gasoline) are presented in Table IV. Five tests for each car/
engine combination matching the St. Louis County vehicles were
picked at random from the files.
Drive.ability during tests was typical of lean operation, with
slight hesitation on tip-in, stretchiness on accelerations,
and surging during cruise.
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Table I
1972
Car Number
Proposed Federal Procedure
(Ceid Start)
Mass ,
HC (FID)
grams/mile
CO
NOX
Dodge 23
Dodge 30
Rebel 29
Rebel 28
Dodge 23
Dodge 30
Plymouth 27
Dodge 24
Ford 26
Ford
Plymouth
§ Dodge 1
Rebel
2.92
3.03
2.69
3.26
2.04
2.71
2.47
2.21
2.41
Average Values
2.41
2.36
2.98
39.4
36.78
24.52
6.20
2.43
18.85
3.66
3.86
4.23
4.23
7.20
15.36
3.59
2.39
2.29
2.95
2.78
2.04
3.39
3.32
1.78
1.78
2.88
2.62
1 First tests of Dodges 23 and 30 excluded.
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2 HOT SEVEN MODI IYCLES
1970 Federal Procedure
(Continuous- Analysis)
Concentration
Mass, grams/mile
Constant Volume Sampling
ftVS)
Procedure
" »
Mass, grams/mile
Car Number
Dodge 23
Dodge 30
Rebel 29
Rebel 28
Dodge 23
Dodge 30
Plymouth 27
Dodge 24
Ford 26
HC
ppm
200.0
275.1
213.5
305.5
287.7
272.1
313.0
236.2
291.3
CO
0.25
1.35
0.78
0.32
0.07
0.37
0.23
0.22
0.28
NO
ppm
1808.9
740.4
727.7
889.6
1097.9
983.2
1466.5
1362.3
582.8
HC
2.54
3.49
2.71
3.87
3.65
3.45
3.61
2.99
3.97
CO
5.78
31.16
17.96
7.43
1.65
8.46
5.05
4.95
7.11
NO
7.05
2.89
2.83
3.47
4.28
3.83
5.22
5.31
2.44
HC CO
No Data
No Data
No Data
No Data
No Data
No Data
2.86 4.22
1.99 3.25
3.63 5.89
NOX
3.08
2.93
1.83
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Table III
1972 Proposed Federal Procedure
(Cold Start)
Average of Four Tests Each
Gasoline Powered Vehicles
Mass, grams/mile
Car Make HC CO NOX
Ford 3.12 28.46 3.58
Plymouth
§ Dodge 3.39 30.45 3.63
Rambler 3.04 31.47 3.08
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Table IV
*
Certification and Surveillance Data
2 Hot Seven Mode Cycles
HC CO
ppm I
Ford 302
191 0.46
211 1.03
200 .72
/ 194 .66
242 .55
Average TOT 0.68
Plymouth § Dodge 318
151 .38
" )' 202 .30
177 .50
222 .19
126 .56
Average 176 .35
Rambler 343
193 .72
201 1.07
193 .48
163 • .53
190 ••••• .93
Average 188 .75
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