Just a general question. I have a 379 (40 over 400 with a 350 crank) that has speed pro forged Pistons with a -14 cc dish. I want to keep the static compression as close to 9.5:1 as possible. Anyone know if Felpro or any other brands offer a head gasket at .035 compressed thickness or less ??? Trying not to go with the expensive cometic brand. Thanks for any advice

 

What's your deck clearance?

 

Fel Pro makes steel shim gaskets that are .015" thick... they are cheap, too.. i think the stock 400 gaskets were .025" thick..

the size of the bore in the gasket makes a big difference in the final compression ratio, too, so try to look for spec for how many cc's the bore is.

 

The block other than the over bore is factory. Stock deck clearance should be .025 if I remember. But I have a set of those same gaskets I was going to use for a dished piston 305. They aren't drilled for the steam homes and those gaskets will over hang the bore. Which may
Not hurt anything. But I was trying to find a gasket with a bore of 4.166 to 4.200 . This is going to be a street machine so that's why I don't want a gasket that's going to get the CR to much more than the 9.5:1 area

 

Yes, the stock deck clearance WAS .025", -.000 -.010" or so. But that's not what you have. Your parts (pistons specifically), which are one of the major factors that determine that, are not stock, therefore your deck clearance might also not be.

What's yours? (as in, MEASURE IT)

Then and only then, you will know what compression you will have with any particular gasket. Don't guess, don't assume, MEASURE.

 

You would be correct in that statement. Even with factory cast Pistons the deck clearance may or not be the same from one cylinder to the next. I'm not concerned with exact measurements. This is not a race motor that has to be disassembled and checked after a win. Just a general question regarding a particular head gasket that I wish to use. Thanks for the help

 

.039" is about the thinnest you are gonna find in a std. cheaper gasket with that bore size.

Fel pro... makes a few 4.166 - 4.200" bore x .039" thickness, Mr. gasket has 1 or 2 in that size.

If you want thinner, you are looking at cometic

 

That's what I have found so far. I was hoping maybe someone might know a brand I didn't think of yet. I appreciate the help