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 ------- 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. ' ------- 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 ------- 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 ------- 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. ------- 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 ------- |