View Full Version : Thinner head gasket with cam
04-08-2012, 07:26 PM
Im running a 305 with comp cams xe268. It runs great by the way. The motor has flat top pistons, and stock, ported heads. Ive been thinking about a thinner head gasket to boost compression. Should I be concerned about the valves hitting the pistons?
04-08-2012, 08:38 PM
If the block is stock the pistons are probably close to .025 in the hole, a .015 compressed gasket should be fine (stock replacements are typically around .040").
04-08-2012, 09:35 PM
Just be aware that running a .015 shim gasket it will rely more one the block and head mating surfaces to be more flat and true that a .040 gasket will. I'm during here looking at a 120k 350 that a set of Fel Pro 1094s didn't live 10k on. Deck surfaces were impeccably cleaned before they were installed, but just clean wasn't good enough.
04-09-2012, 08:59 AM
great info. thanks guys. my main concern was whether or not the valves will hit the pistons. also thank you for bringing the deck surface topic into play. I will keep that in mind when making the modification.
04-09-2012, 02:31 PM
ok so i have one more question. I guess the word "shim" just doesnt fit right. Is the shim gasket actually a gasket? Or is it just used as a shim with a regular head gasket? I guess i need to know more about these shim gaskets before i get too excited and mess this thing up.
04-09-2012, 06:16 PM
No, it is not a' shim' so to speak, but it does not compress like a stock replacement' composition' gasket like your standard parts store replacement gasket. That is why it is more picky about surface finish and flatness.
04-10-2012, 10:40 AM
ohh ok. I get it now. some of the terms used confuse me sometimes. thanks for the info
Powered by vBulletin® Version 4.2.0 Copyright © 2013 vBulletin Solutions, Inc. All rights reserved.
SEO by vBSEO