The involute lug drive snowmobile track is a major step forward in the technological improvement of snowmobile performance. New materials, new designs, and new methods are employed to fabricate a snowmobile track that has outstanding performance characteristics. The liquid cast polyurethane system makes possible improved track carcass construction, maintaining the ultimate physical properties required to make a long-lived, efficient, power transmitting snowmobile track.This paper discusses the engineering principles of snowmobile locomotion and how they apply to the improved design of the involute lug drive track. The relation between material, physical properties, construction methods, design, and track performance is developed. Fatigue characteristics of textile tensile cords are presented showing correlation to field and laboratory track testing. The exceptional polyurethane involute lug track and drive wheel characteristics are compared with conventional tracks. Problems associated with snowmobile track field testing and evaluation are discussed. The engine horsepower loss due to less oxygen available at higher elevations is graphically compared to SAE elevation correction factors. The peculiarities of alpine snow conditions are presented as the ultimate proving grounds for snowmobiles.