Research Projects

Project at a Glance

Project Status: complete

Report Published July 1998:

Title: Demonstration of a heavy duty vehicle chassis screening test for compliance testing heavy-duty engines.

Principal Investigator / Author(s): Clark, Nigel N

Contractor: West Virginia University

Contract Number: 94-347

Research Program Area: Emissions Monitoring & Control

Topic Areas: Mobile Sources & Fuels


Emissions testing of new heavy-duty engines is performed to ensure compliance with governmental emissions standards. This testing involves operating the engine through the heavy duty diesel engine transient Federal Test Procedure (FTP). While in use engine emissions testing would be beneficial in aiding regions to meet standards dictated by the Clean Air Act, the process of removing the engine from the vehicle, fitting it to an engine dynamometer, testing and refitting the engine in the chassis, combined with costs associated with removing the vehicle from service, is prohibitively expensive. A procedure for screening engine emissions testing with the engine in the vehicle using a chassis dynamometer was developed to mimic the FTP. Data from two engines and vehicles (a 195 hp Navistar T 444 E in a single axle straight truck and a 370 hp Cummins N-14 in a tandem drive axle tractor) is presented as well as correlation between engine and chassis emission tests. Also included was data gathered to gauge the effects of engine tampering and malfunctioning on emissions levels. It was concluded that engine and chassis emissions levels were well correlated with respect to oxides of nitrogen, but less well so with respect to particulate matter.


For questions regarding this research project, including available data and progress status, contact: Heather Choi at (916) 322-3893

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