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

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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.

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                            -2-
Closer repeatability might have been achieved if the tests
had been run back to back eliminating the variables of delayed
testing.

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                              -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

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