Quote Originally Posted by CraigCantwell View Post
The CG numbers for the engine sound a bit off. From your description, the CG for the engine and prop combination is 9.5 inches from the firewall? That would indicate that the the CG point of the motor would be just about at the trailing edge of the back cylinder. CG should be more like the aft side, or center of the forward cylinder.

CG of the engine sans prop --- you are very close to spot on. It balances almost exactly between cylinders 1 and 2----actually somewhat closer to the leading edge of 1. (this includes the dizzy, oil pump, y-pipe, Revmaster carb, but not the prop. We actually balanced it on a dowel rod on the welding table to prove it to ourselves....).

As the engine is mounted on our temporary mount---the balance point of the engine is exactly 10.5 inches ahead of the front face of the firewall (our datum) so (-)10.5 inches for the moment.