AmSnow.com is now SnoWest.com
Outboard Marine Corporation (OMC) in Milwaukee, Wis., started building snowmobiles in 1965 and made Evinrude, Johnson and Snow Cruisers from 1965 to 1976. In the early days, OMC used its own 2-stroke boxer-type opposed cylinder horizontal engine, which had a displacement of 362cc and produced 14hp.
Over time, OMC made larger boxer-type opposed engines with different cc and greater horsepower to keep up with competition. The first American-built rotary combustion engine was built under a license agreement from Curtiss-Wright Corporation for Evinrude OMC to build engines expressly for Evinrude snowmobiles. OMC might have used the technology in its outboards in the future, but they initially worked hard to make a quiet snowmobile.