- Jan 13, 2011
- United States
A relatively mild, built, used, pulling engine. Started with a 25 HP Kohler Command, bored and stroked to 50.5 cubic inch. Mid West Super Cub 3" crank, Billet rods, 4000 RPM cam kit. Adjustable main jet carb. Adjustable billet aluminum flywheel. Listed at $2,795 (starting from a new engine, you could not build this engine this cheap), advertised 50 HP. Weight is unknown, but my educated guess (based on book weight for a "dressed" engine, and the reduction in flywheel weight, plus a guess at the removed shrouding) that its about 90 lbs as it sits. Don't know what RPM that HP number represents, but I'm guessing 4000 RPM, so you'd need a PSRU to get all of it, but with that displacement, you'll surely get North of 30 at direct drive RPM (the stock engine was rated at 3600 RPM). But for how long? With a forged crank, forged pistons, billet rods, heat dissipation of the heads will be the limiting factor. This engine has an oil cooler, and pressure lubrication.