.028 GMPP head gasket question

[pkj]

i have a 78 van 305, 145 h.p. engine that i am warming up. i know all about the boat anchor stuff. but its mine and i am going to make it run decent. had a couple of forf 302s that i got runnin strong. the current heads are 60 cc stock. i have a set of 601s with 1.94 int. 1.6 exh. valves. i think the motor is 8:5to1 c/r if i am right. the 601 heads are 53 cc i believe. that should give me 9:2 to 1? will i benifit with the .028 GMPP head gaskets? is there another side of the coin using them? thanks, pkj

[Green Machine]

Many 305's had the .028 gaskets factory, make sure to get the ones for the 305 bore, not a 350. Ideal piston to head clearance is about .040, the .028 gaskets should give about .53, unless you can find steel shim head gasket for the 305 bore, I can't find them anywhere. Most rebuilder gaskets run about .040, but I had some Victor a while back that were .050, did not use those. You would have to CC those 601's to know for sure, since the larger valves should have had the chambers enlarged for clearance.