Designing a Clean, Quiet, Fuel Efficient High Performance Two- Stroke Flex Fuel Snowmobile

The University of Wisconsin-Platteville (UW-P) Clean Snowmobile Team has successfully designed and constructed a quiet, environmentally friendly, high performance snowmobile for the 2011 Society of Automotive Engineers (SAE) Clean Snowmobile Challenge (CSC). Built on a 2009 Ski-Doo REV-XP chassis, this machine features a 594 cc direct-injection (E-TEC) two-stroke engine. Utilizing a Split Second Electronically Controlled Unit, as a fuel management system, we are able to decrease exhaust emissions and improve fuel economy to near stock engine power while allowing operation on any blend of gasoline and ethanol between E20 and E29. The emissions output is further reduced by utilizing a pre-burn catalyst system customized for this engine by Tikka Race. A modified expansion chamber, muffler system, and the addition of sound absorbing material are respectively used to reduce exhaust and engine compartment noise. These modifications achieved UW-P’s reliability, efficiency, and noise goals, as testing done prior to competition showed the snowmobile getting 14.1 mpg (6 km/L) on E25 ethanol fuel, creating 116 hp (88 kW), and emitting 80 % less HC when compared to stock emissions numbers.