So, rocket Ron, you can take a 31" Briggs, required to run as cast head, stock springs, pushrods and valves, Stock rocker arms, cam, valves, crank, piston, rings, intake, carburetor, ignition system, and say you have a proven combination. I'm not doubting what you can do without rules, but the class I'm in has plenty of them. Even if you had a magic bullet for that combination, I'd not expect you to release the cat, My guess is, you won't waste your time with something you can't sell parts on. I'm trying to learn, if you've no productive input, you are of no help, therefore useless to what I'm doing.