Does anybody make a thicker head gasket for a 65 300? Or can I stack the steel ones? I ask because I have 10.25:1 comp. and I dont want my engine to ping and knock because of poor gas. I am not sure if I can polish the chambers good, so I would rather not attempt it. Thanks, Philip
My 340 has the same compression and has pinged since the 1970's despite every advice I could try. I would recommend a racing fuel mix or that Outlaw brand octane booster. Both have reduced my pinging by maybe 75%. My next move will be to install a Holley water injection kit I just bought on eBay. To answer your question, I haven't seen head gaskets sufficiently thick to offset the compression.
The new-in-box Holley kit cost me $46 plus $7 shipping. It was probably made in the mid 1970's, but never used. The Edelbrock water injection kits from the 1970's are more sophistocated, but are more rare and seem to cost about $125 on eBay in unused condition.
Yes - the Felpro set for the Buick 300 about 2 or 3 times thicker...that's what I'm using with the 10.25:1 pistons. I think the felpro set is .038 & stock is .010 (something like that)
I wish 91 octane was that cheap, it's 2.32 out here. All I plan on doing is what you did, I don't want to open the heads up, I just want to polish them, I was thinking about using a 3m wheel instead of a wire brush, I think it will polish it more without being to agressive.
I have been running 10.25 since '84 on 92 gas with little or no pinging but I have kept the the pistons and head chambers clean. On my rebuilt last year I had heads cleaned and scrubbed the piston tops with a scotchbright until they were clean. I had bad luck with some "sandwich" gaskets years ago- they leaked apon starting the engine and it didn't get any better after re-torqueing. I only use steel with oil now. It is possible that the holley carb runs richer and lets me get away with higher compression on high load situations.
