Development of a Direct-Injected Two Stroke Snowmobile Using E85 Fuel

The University of Idaho’s entry into the 2008 SAE Clean Snowmobile Challenge (CSC) was a direct-injection (DI) twostroke powered snowmobile modified to use blended ethanol fuel. The modulated and battery-less direct-injection system used to decrease exhaust emissions and improve fuel economy maintained near stock power output of the engine. The emissions output was further reduced using an oxidation catalyst located after the exhaust silencer. Noise from the engine compartment was reduced by custom-carbon fiber hood and side panels, which allowed placement of extra sound absorbing materials. Pre-competition testing had the snowmobile entering the 2008 SAE CSC competition weighing 580 lbs (263 kg) wet, achieving 13.25 mpg (5.63 km/L) running on blended ethanol fuel, and a J-192 sound magnitude score of 80 dBA.