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Head gaskets

Chevy305

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Hey so with my 355 that I am building its almost time for heads but I have no idea what I want/need for gaskets. I picked these out, but could someone tell me what I need for a .030 over 350 that will be pushing between a 9.6:1 to 10:1 compression.

http://www.jegs.com/i/Fel-Pro/375/1142/10002/-1

375-1142.jpg
 
Compression ratio sounds a bit high for pump gas unless you are using aluminum heads. Gasket material and thickness varies. Generally you choose a gasket to match the CR you are shooting for.
 
What you need to measure, is the distance from the top of the block (where the head's bolted) down to the highest part of the piston, with the piston at TDC.

This can be done w/the depth function of a dial or veneer caliper but is more easily (and accurately) done w/a micrometer that bridges the bore (depth mic). But it doesn't have to be accurate down to 0.0001", either.

Better than me struggling to describe the deal, here's a brief description along w/a calculator to figure what it is: http://www.rbracing-rsr.com/squishcalc1.html

"Squench" should be close to 0.040" as is possible, but sometimes this figure isn't possible w/the parts that are on hand.

To significantly change the deck height, you can use gasket thickness to compensate. 0.040" is a good happy medium... the tighter you go the better BUT the tighter you go the more probable interference will occur. Hope this helps.
 
I understand all the thickness stuff but I was really looking for what material gasket should I use? You know such as multi-layered steel, or copper, or whater else they offer?
 
Use a standard Fel-Pro composite type gasket. Keep FAR AWAY from the MLS gasket unless you're having the block AND heads machined with the proper finish for an MLS gasket. Also most stock SBC and BBC engines have the pistons about .020"-.025" down the bore at TDC so I would recommend that you use a compressed gasket thickness of .039" and call it good. The ideal quench is .040" but you cannot achieve that number without zero decking the block.
 
Use a standard Fel-Pro composite type gasket. Keep FAR AWAY from the MLS gasket unless you're having the block AND heads machined with the proper finish for an MLS gasket. Also most stock SBC and BBC engines have the pistons about .020"-.025" down the bore at TDC so I would recommend that you use a compressed gasket thickness of .039" and call it good. The ideal quench is .040" but you cannot achieve that number without zero decking the block.

Thanks, I never had the block decked so I will not use the MLS gaskets. I guess thats good because it saves me $$ :deal:

Ok time to take some measurements and do some searching. :D
 
Use a standard Fel-Pro composite type gasket. Keep FAR AWAY from the MLS gasket unless you're having the block AND heads machined with the proper finish for an MLS gasket. Also most stock SBC and BBC engines have the pistons about .020"-.025" down the bore at TDC so I would recommend that you use a compressed gasket thickness of .039" and call it good. The ideal quench is .040" but you cannot achieve that number without zero decking the block.


I`ve had good luck with these in the past, and it`s what I`ll use when I do my heads.
 
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