EPA-AA-TEB-80-15
Prototype 1981 Peugeot Diesel Emissions Tests
by
Edward Anthony Earth
March 1980
Test and Evaluation Branch
Emission Control Technology Division
Office of Mobile Source Air Pollution Control
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 fuel economy or both. EPA invites
developers of such systems to provide complete technical data on the system's
principle of operation, together with available test data on the system. In
those cases for which review by EPA technical staff suggests that the data
available shows promise, confirmatory tests are run at the EPA Motor Vehicle
Emission Laboratory at Ann Arbor, Michigan. The results of all such test
projects are set forth in a series of Test and Evaluation Reports, of which
this report is one.
Peugeot inquired about possible EPA interest in testing a prototype 1981
diesel with progressive EGR and turbocharging. Since EPA had tested only a
limited number of EGR equipped Diesels, arrangements were made to run an
evaluation program. The vehicle arrived in December and was tested during
December 1979 and January 1980.
The conclusions from the EPA evaluation test can be considered to be
quantitatively valid only for the specific test car used; however, it is
reasonable to extrapolate the results from the EPA test to other types of
vehicles in a directional manner, i.e. to suggest that similar results are
likely to be achieved on other types of vehicles.
Summary of Findings
This 1981 Peugeot Diesel (progressive EGR with turbocharging) met the
statutory 1981 standards for gaseous emissions. NO levels (1.04 gm/mi) were
actually slightly above the standard of 1.0 gm/mi tut met the 1981 standard
when this value was rounded off. (Note: The NO value is not corrected for a
NO deterioration factor).
X
Particulate emissions were 0.324 gm/mi, thus readily meeting the 1982 light
duty Diesel particulate standard of 0.6 gm/mi.
Fuel economy was 28.5 mpg for the FTP and 38.3 for the HFET.
The vehicle had good driveability.
Test Vehicle
The test vehicle was a prototype 1981 Peugeot 504 Diesel. The vehicle uses
the 140 CID XD2S engine with a turbocharger. EGR is used for NO control.
The vehicle weighed 3175 Ibs and was tested at an inertia weight of 3500 Ibs.
The vehicle was equipped with a four speed manual transmission.
The vehicle's Bosch mechanical fuel injection is modulated at full load to
compensate for turbo boost pressure and altitude. A boost pressure regulated
full load stop limits the maximum fuel delivery. An altitude compensated full
load stop reduces the full load fuel delivery to be proportional to the
barometric pressure. '
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The vehicle's EGR system is a progressive EGR unit. At low load there is up
to 35% EGR. The percentage of EGR progressively decreases as engine load is
increased with there being no EGR at heavy loads. The system incorporates a
vacuum converter fixed to the injection pump to provide an EGR vacuum signal
proportional to accelerator pedal position. An electronic system overrides
this vacuum system and eliminates EGR under heavy loads at both low and high
engine RPM.
A Garrett AiResearch turbocharger is used to provide improved performance. A
wastegate limits the absolute manifold pressure to 1.6 bar (1.6 times
atmospheric pressure) for a net boost of .6 bar (9 psi). Injection pump
timing is modified to increase low speed fuel charging and thereby increase
low speed torque. The compression ratio is reduced from 22.5 to 1 for the
naturally aspirated engine to 21.5 to 1 for the turbocharged engine.
Peugeot claims that, when compared with their naturally aspirated Diesel
engine, this turbocharged Diesel has: improved performance and driveability, a
reduction in noise, reduction in pollution and no loss in fuel economy.
Additional information on this vehicle is given in the vehicle information
data sheet.
Test Procedures
Exhaust emission tests were conducted according to the Federal Test Procedure
(FTP) described in the Federal Register of February 1, 1979 and the EPA
Highway Fuel Economy Test (HFET) described in the Federal Register of
September 10, 1976. The vehicle was tested using an EPA light duty Diesel
particulate sampling system.
To evaluate the effectiveness of the EGR system, Peugeot suggested that the
vehicle be tested both with and without EGR. EPA concurred and thus the
vehicle was tested both with and without EGR.
Prior to testing the vehicle was given a specification check and visually
inspected. The idle speed was checked and found to be within specification.
Several engine bolts were loose and had to be tightened prior to testing.
Test Results
The FTP results are given in Table I and the HFET results are given in Table
II. The tests noted with an asterisk were tests that were performed at
non-standard conditions. The data on these tests was included for
completeness. The vehicle's manual transmission is nominally shifted at 16,
27 and 35 mph. However, because there are varying acceleration rates in the
FTP cycle, Peugeot modified the shift schedule to be more compatible with the
engine power output. Therefore, several shifts occurred at slightly different
speeds in the FTP. This is an acceptable practice and thus many manufacturers
specify shifts at different speeds throughout the driving cycle.
Average FTP emissions were HC 0.23 gm/mi, CO 1.34 gm/mi, NO 1.04 gm/mi and
particulate 0.32 gm/mi. Fuel economy was 28.5 mpg. Thus with the roundoff,
this vehicle met the level of the 1981 NO standard of 1.0 gm/mi.
X
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It should be noted that this NO value is uncorrected for the NO
deterioration factor. Also, Peugeot has appled for a NO waiver to 1.5 gm/mi
for their 1981 light duty Diesels. The original Peugeot request has been
denied but Peugeot has reapplied for a NO waiver. This second request is
currently under review by EPA.
When EGR was disconnected, the FTP HC emissions were unchanged, CO emissions
decreased 12%, NO increased 90%, particulates decreased 18% and FTP fuel
economy was unchanged. The FTP tests with shift speed.s at exactly 16, 27, and
35 mph were unchanged from the baseline tests.
Peugeot tested the vehicle both with and without EGR at their own test
facility. Their test data showed similar results.
The average HFET emissions were HC 0.06 gm/mi, CO 0.62 gm/mi, NO 0.72 gm/mi
and particulates 0.23 gm/mi. Fuel, .economy was 38.3 mpg.
With the EGR System disconnected, the change in HFET emissions was nearly
identical to the effect on FTP emissions. Namely HFET HC emissions were
basically unchanged, CO emissions decreased 14%, NO emissions increased 122%
and particulates decreased 22%. HFET fuel economy was unchanged. The HFET
test-with no shift to 4th gear caused HC, CO, NO and particulate emissions to
be significantly increased over the baseline and EGR disconnected test
conditions. Fuel economy decreased significantly.
The. inverse relationship between NO and particulates exhibited by this
vehicle for both the FTP and HFET has been seen in other diesel vehicles.
This vehicle was given a limited road test in the baseline configuration
'(turbocharged with EGR). The vehicle had good driveability and good
acceleration.
Conclusions
The test vehicle met the gaseous standards for 1981 light duty diesel
vehicles. The vehicle also met the 1982 particulate standard of 0.6 gm/mile.
However, the NO level was at the level of the standard and realistically the
engine would have to be recalibrated for lower NO levels for the vehicle to
be certifiable at the 1981 NO level of 1.0 gm/mi. X
X
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Gaseous emissions and particulate results are summarized below.
Table I
19-8.1 Turbocharged/EGR Prototype Peugeot 504 Diesel
FTP Mass Emissions
grams per mile
Test No.
With progressive
80-0780
80-0781
80-0936
EGR disconnected
80-0878
80-0880
With progressive
80-0776*
80-0779*
HC (HFID)
EGR
.28
.20
.22
.24
.22 .
EGR, shift at
.26
.23
1981 Turbocharged/EGR
With progressive
80-0777
80-0778
EGR disconnected
80-0881
80-0882
EGR disconnected
HFET
EGR
.06
.06
.09
.09
CO
1.37
1.32
1.32
1.16
1.18
16, 27, 35
1.31
1.35
Table II
Prototype
co2
357
351
354
350
356
mph only
357
349
Peugeot 504
NO
X
1.04
1.05
1.04
1.96
2.00
1.08
1.01
Diesel
MPG
28.3
28.8
28.5
28.9
28.4
28.3
28.9
Particulates
.315
.333
.268
.262
.312
.329
Mass Emissions
.63
.60
.52
.54
269
260
271
265
.73
.70
1.60
1.58
37.7
39.0
37.4
38.2
.218
.236
.172
.172
, no shift to 4th gear
311
2.04
32.5
.343
* Non-standard test condition, test data included for information purposes
only.
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Test Vehicle Description
Chassis model year/make-Prototype 1981 Peugeot 504 Diesel
Engine
Type ..;.-.- Diesel inline, 4 cylinder
Engine family XD2S
Bore x stroke 3.70 X 3.26 in/94.0 X 82.8 mm
Displacement 140.6 CID/2.3 Liter
Compression ratio 21.5:1
Maximum power @ rpm 80 hp/59.7 kW
Fuel metering Bosch mechanical fuel injection
Fuel requirements Diesel No. 2, tested with Diesel No. 2
Drive Train
Transmission type 4 speed 'manual
Final drive ratio 3.31:1
Chassis
Type 4 door sedan
Tire size Michelin 175 HRxl4
Inertia weight 3500 Ibs.
Emission Control System
Basic type Progressve EGR
Garrett Turbocharger
US. GOVERNMENT PRINTING OFFICE: 1980- 651-112/0245
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