Oscar Westermayer built the W5/30 engine as a replacement for classic American engines like the Continental O-200. It produced 100 hp at 2750 rpm.

“W5/30”

-The novelty of this engine was that while the cylinders were air-cooled, the cylinder heads were liquid-cooled with ethylene glycol.

-They manufactured the W5/33 version from 1989 to 1992.

-In fact, these were adaptations based on 1600cc VW engines.