[JRShaw]

There is a model B crankshaft (counterweighted) as well as cam in my Late '31 Truck. I am told that a non-counterweighted engine will idle slower. This is from a friend that I have known for a very long time. He has had National Winner A's. We will find out as there is a standard A crank in my Diamond engine Standard Roadster (work in process). Not sure if this will help you or not.