73-10 Exhaust Emission Analysis of Two Wankel-Powered Cars Furnished by the U.S. Army Tank/Automotive Command September 1972 Leonard D. Verrelli Power ^Systems Section Test and Evaluation Branch Environmental Protection Agency ------- Background The U.S. Army has purchased two Wankel-powered passenger cars to evaluate the rotary engine for military application. The evaluation will include driveability, fuel economy, exhaust emissions, and durability. EPA was asked to provide the emissions measurement portion of the evaluation. Vehicles Tested The test cars were the Mazda R100, with a 60 cu. in. rotary engine, and the NSU Ro80, with a 995 cc rotary engine. Both vehicles were received in stock condition.. Test Program Testing was -accomplished using the 1975 Federal Test Procedure (3-bag) with the inertia set at 2250 Ibs for the Mazda and 3000 Ibs. for the NSU. Instrumentation was as specified in the Federal Register. Constant Volume Sampler (CVS) bag samples were analyzed for unburned hydrocarbons (HC) with a FID, for CO and C02 with NDIR, and for nitrogen oxides (NOx) with chemiluminescence (CL), An attempt was made to. measure hydrocarbons (HC) using a heated FID but numerous equipment malfunctions precluded this type of measurement. Test Results The emission results are presented in the Appendix of this report. None of the tests approach 1975 or 1976 required levels However, relatively low levels of oxides of nitrogen were achieved. Conclusion „... To provide a solid baseline from which to begin the 50,000-mile durability, several more tests should have been run. However, there is a wealth of data available on the Mazda rotary through the certification testing. The short time alloted for testing precluded multi-baseline runs. ------- -2- Closer repeatability might have been achieved if the tests had been run back to back eliminating the variables of delayed testing. ------- -3- APPENDIX Cold Start 1975 FTP (all results in grains per mile) Test 8-23 Test 8-28 #1 -72 #2 -72 HC 7.56 4.70 MAZDA CO 41.87 24.48 CO- 506.32 576.42 NOx 1.26 1.25 Calculated Fuel. Consumption 14.6 mpg Test #1 8-23-72 Test #2 Calculated Fuel Consumption 14.9 mpg HC 9.03 7.03 NSU CO 57. 35.' 50 08 co2 499, 529. 52 54 NOx 1.44 1.70 ------- |