273 Hi-Comp Piston Deck Height

It really depends on what you call high compression. Some guys are at -0- deck, mine are at +.060 or out of the block flat tops. I haven't fired it yet to see if I need racing fuel with stock x-heads. My son in law runs domes with valve reliefs in his nova 12:1 and it is wicked. Depends on what you want. My .02 on your engine with stock heads, about 9.5 or 10 to 1. I've seen them in a late 70's 360 about 1/4 inch down, probably 8 to 1. But I'm just an old dumb ***. Walt