Development Solutions to a Cleaner, Quieter, Two-Stroke Snowmobile

This paper describes the design strategy used by the University of Waterloo's Team Eco-Snow to modify a stock snowmobile in order to compete in the Clean Snowmobile Challenge for 2002. A two-stroke snowmobile is modified to operate more cleanly, quietly, and without sacrificing performance. Excessive noise emissions were Team Eco-Snow's major concern. Noise reductions between 9 and 16 dBA are achieved. Drivetrain and engine efficiency are improved through reduced track frictional drag losses, reduced peak operating engine speed, increased compression ratio, and port modifications that redirect tumble and enhance swirl. Emissions are primarily reduced through an air-assisted catalytic converter system coupled with leaner carburetor settings.