73-3
         Evaluation of the Texaco
Stratified Charge (TCP) M-151 Army Vehicle
            August 1972
           Henry L. Gompf
    Control Device Evaluation Section
      Environmental Protection Agency

-------
Background

      In testing this spring at the Texaco Laboratories it
was indicated that the TCP M-151 vehicle was consistently
meeting low emission levels dictated by 1976 Federal emission
standards.  The following emission values are the average
of three tests performed in the Texaco laboratory immediately
prior to delivery of the vehicle to EPA.

       Hydrocarbon                      0.28 grams per mile
       Carbon Monoxide                  0.86 grams per mile
       Oxides of Nitrogen               0.31 grams per mile

As part of our cooperative effort with the U.S. Army and to
expand on our previous evaluations of the emission character-
istics of this vehicle, a confirmatory test program was
scheduled in the EPA laboratory.

Vehicle Tested

      The vehicle tested was an Army M-151 1/4-ton truck with a
four speed manual transmission.  The 141 CID engine was modified
to incorporate a stratified charge, multifuel combustion process,
In addition, an EGR system using a high and low flow rate valve
was installed for oxides of nitrogen control.  Three catalytic
reactors were employed for oxidation of hydrocarbon and carbon
monoxide: a platinum plated swirl reactor, an Englehart PTX
platinum catalyst and a Texaco copper chromite reactor.  The
vehicle was operated on a mixture of Texaco no-lead pump fuel
and 2 percent lubricating oil.

Test Program

      The Texaco version of the stratified charge engine M-151
vehicle was tested three times.  The test procedure used was
that specified for 1975 model year certification.  Details of
this procedure are described in the July 2, 1971, Federal
Register.

      Due to the presence of lubricating oil in the fuel,
additional continuous analyses of hydrocarbon emissions were
made using a heated flame ionization detector.

Test Results

      The following table presents the emission data compiled
during the EPA evaluation.

-------
                 1975 FTP Emission Results
           (all results in grams per mile)
Date

5/10/72
5/11/72
5/12/72
HC*
0.40
Q. 33
0.37
CO
0.27
0.12
0.31
co2
566.2
539.1
549.6
NOx
0.30
0.31
0.30
             Average            0.37      0.23   551.6   0.30
      It should be noted that the TCP vehicle was not capable
of meeting the acceleration requirements of the LA4-S4 driving
schedule.

Conclusions

      The  TCP stratified charge vehicle met the required emission
levels for 1976 model light duty vehicles.   No estimate of
durability can yet be made.
* Due to technical operational problems the results of the
heated flame ionization detector were inconclusive.  Cold
FID data are reported.

-------