Thanx Ed,,,I`ll give you some info on first setup I had,,pump gas 92 octane,,brodix alum block,,afr 305 heads shaved to 114 cc, I think they took .050 off them,,264/272 715 lift @108 L.S.,,flat top piston -3 dome,,piston in the hole .009 cold,,,.019 hot,,,.040 head gasket,,valve to piston int.-.200,ex.-.080,,, (no relieve for ex. in piston) Car ran great at 30 timing never dyno ed but ran 9.50s w/2900 @ 3500 air...Needed new cam(wont tell you how I wrecked other one,,,) anyway new combo will be..same block,,,afr 357 cc heads w/121cc chambers,,,.040 head gasket 4.630,,,cam 268/278 750 lift,,,piston lets say still in the hole .009-c/.019-h...I need to get a piston where I can max out on compression and still run 92 octane pump gas ( I heard a while ago that you could run 10-1 on steel heads, and 11-1 on alum,,but you don`t see that coming from engine builders anymore,,thats why I`m asking the question, about compression,,maybe its from the old days when we had leaded gas and higher octane??? So any way I see Wiseco is making a 15 cc dome piston now for BBC,and thats were I thought I would go,but I don`t want to exceed my compression limit here,,you mentioned piston designs you have-may look into that! so here I am with the compression ratio issue,,I don`t much like getting my hands dirty that much anymore( getting to old for that) so I want to get it right this time and spend more time driving it. I`ve had the car for some 30 years now and started out racing around in the 14 sec range and I`ve been changing combinations since..Time to leave it alone and just race,,I`ve won 2 championships lately,and even a Wally.but with changing things all the time, It`s hard to stay consistant...any way enough jabbering!!! heres where we are,,on the PISTON issue