i am considering FI for my L98 'roc and i got to thinking, im regasketing my engine and i was thinking about what head gasket to run. i was thinking the typical fel-pro with the .038 compressed gasket thickness to not raise boost but then i got to thinking about squish area and i was thinking if i ran a shim gasket which is .015 compressed, that it would increas compression but it would also increase turbulence in the compustion chamber and help deter detonation. Am i right thinking this or should i just stick to the fel-pro and keep the compression down as much as possible? also would the shim gasket keep from blowing out under lower boost apps. i dont ever plan to run more than like 6 lbs. atleast till i upgrade fuel system considerably and go with a forged bottom end.

thanks
*Eric*

 

I was about to use some cometics in my engine to reduce my CR and had asked Lloyd Elliot about this, here is his reply

"Curt,

The stock LT1 heads are about 56 cc. I can get them to about 59 cc and that is about it. Make sure and do not use a thicker head gasket to lower compression. The quench is more important than lowering compression.

If you are running 6-10 lbs of boost, the car will run great with the right cam and getting the quench right. As you build more boost (12 to 22 lbs), you would like to lower compression as much as possible and have more area in the cylinders that are "boosted". the lower the amount of boost, the less this matters.

With a low amount of boost, some people like the feel of the LT1 heads and boost since they have good compression still and the car will run better until the boost build up. Once we reach full boost, the lower compression is better but if aftermarket heads are not in the budget, the LT1's will have to do. It really depends on how much boost you are running and how quickly the boost comes in. If you are not at full boost until a high RPM, the added compression is a good thing until that point.

Lloyd Elliott
972-617-5671
Eportworks.com"

 

so basically i was along the right line of thought, that is why people build zero deck motors is to creat more quench and returblate the a/f mixture, but now i am wondering how durable the shim gaskets will be, because the last thing i want is a blown head gasket... also im going to clean up the chamber so anything i would gain in comp. from the thinner gasket will prolly be lost what it taken out of the chamber, but the piston will be closer to the head so quench will be increased still.
i think im going to order the shim gaskets tonight and wait to see if i get any more responses in either neg. or pos. form before i put it back together.

thanks
*eric*