In a message dated 6/23/05 10:05:07 PM Eastern Daylight Time, pp2 at 6007.us writes: << Are the valves larger ? >> Much larger. makes the combustion chamber look just like a Chevy double bump head. Besides using a 95 hp stick distributor, and cut deck height; another way to keep a 140 from pinging is a long duration/high overlap camshaft. Warren