Summit 383 Top Performer kit

Either one will physically fit your engine. The difference is in the cc's of the combustion chambers. The 20862 kit has larger combustion chambers and would result in a net drop in your compression ratio. The 208622 has smaller combustion chambers to maintain your cr. If you're rebuilding the bottom end, your piston choice would dictate which heads to use.


Well............I've checked combustion chambers on some 516 heads, they poured to 84 cc's. Long way from the supposed 73.5 cc factory spec.