As luck would have it, I blew a head gasket. I am planning to do some porting,exhaust and intake work while the motor is down.I heard they make head gaskets that bump up compression a bit. Anybody know if they are good or blow easy. Part numbers would also help.

 

FelPro has a thin one, compresses to like .016" instead of .041", I have Summit catalog.. hold on... NOt in that one. Gotta go to Jeg's or PAw. Has more #'s. Sorry. You'll find it.

 

Fel-Pro #1094 .015 thick rubber coated. .039 thick gasket at 9:1 9.5:1 with the .015 with a 4.030 bore. From CHP 10-99

 

Oops, I meant .015. Yeah, .015, that's what I meant. BE careful with that gasket, too, becasue I have seen some intake port misalignment/leaking because the heads are so much "lower". c-ya

 

There was an article recently in one of the mags that did just such a comparsion as you are considering. Took an engine and swapped head gaskets to see the effect of the increased compression.

If I remember correctly, they used three Fel-Pros of different thicknesses and one GM. The GM gave disappointing results and the article suggested that there is a 'sweet spot' for quench that the GM gasket missed.

Overall, power increased as compression went up (thinner gasket) but the GM gasket didn't show the expected results.

No mention was made of the durability of the gaskets, but I suspect that the thinner you go the more concerned you'd have to be with your block and head surfaces being truely flat.

Remember, higher compression isn't the only consideration. Proper quench is also very important to make the engine less sensative to detonation. You'll have to check to see what your deck height is to make sure that with the gasket you plan to run quench falls in the desirable range of .035 (minimum) to .040 (maximum).

Normally a zero deck is used in combination with a .038/.040 head gasket to give the ideal quench. Compression is obtained byb reducing combustion chamber ccs (best) or piston dome (least desirable).

Not sure about your combo, but piston to valve can be a concern too if a cam is installed with a much higher lift.

Hope this helps,

Jake - not to be confused with my namesake.



------------------
1986 Corvette Coupe, 415 CID, Edelbrock 6073s, ZZ9