Ok you guys i have a couple questions?
Does anyone know were i could get thicker than stock head gaskets for a lt1 motor? how thick is it?
How much can i open up the stock 54cc heads in the chambers.... like how much material can i remove succsefully without damaging the heads...

What iam trying to do is open up chambers in the stock heads as much as i can so i could run a little more boost on a bugdet with a vortec supercharger i just picked up for a good price.....

My stock block has 89,000 miles on it so iam thinking if i could bring the comp down to about 9:5:1 ratio i could safely run maybe 11-12 pounds of boost... of course with proper tuning and meth injection......

 

Check with the guys who port heads but I think they can take out a few ccs. I did that to mine but they are AFRs so it isnt a direct comparison. Too thick of a gasket isnt good, but if you go that route with FI you can use a good quality MLS gasket and they can make the center section thicker if you want - still i wouldn't go over .050 or so - not sure what others have done here. When I was doing all this on my engine, I did a spreadsheet to do the calculations - I ignored the area on top of the ring though, but it worked pretty well. I cc'd the heads and pistons to make sure what I had and I ended up with really close to 9:1 static comp.

 

See iam really trying to find out whats the lowest comp possible, without changing pistons????

 

you'll probalby lose more detonation resistance by killing your quench than you'd gain by a marginally thicker head gasket.

Stock LT1's run with pistons 0.15" to 0.030" in the hole... varries a bunch depending who you're talking to, but 0.025" in the hole is normal. Gasket is 0.019" in the iron-head B-body LT1's and L99's, but aluminum heads use a GM gasket that I THINK is about 0.029"... do a search to be sure. The most common aftermarket gasket is the Felpro 0.039" which works well with flush pistons (usually in a 0-decked, 9.000" block).

You may be able to fly cut the pistons a touch, but I'm pretty sure most shops would pull the pistons for that anyway (unless you're using the Isky value-tool)... if you're pulling them, you're better off with replacing the pistons with a more turbo-friendly ring package and piston design (i.e. -10cc dish ).

Porting the LT1 heads is fine, mostly jsut clean up, but you're gonna have stability issues if you get some crazy idea of pulling 10cc's out of there. If you're looking for big boost, the Trick Flow heads with large chambers and extra thick decks would be useful.

Without changing pistons you're assuming the block is fine, the pistons are fine, the rings are ok, and the heads aren't warped and need to be decked (though most Al heads can use this after being used and removed). 6psi isn't an issue on a stock set up, but pushing 10 will probably require an intercooler and lower compression... not exactly a stock block set up on the cheap.

Don't focus on psi... look at air flow/hp. I suppose the best question is what compressor will you be using, and what are your hp goals.

 

Thing is you will not be adressing a key cause of failure. The rings can get too hot and close the gap causing all hell to break loose. Poor chamber work can cause increased tendancy for detonation which will again destroy pistons.

Either live with lower boost or build the shortblock.

Also understand boost is the measure of how much air is NOT moving through the engine but is instead accumulating in the intake.

 

Thank you guys for all your input....... i guess iam going to build the motor then.... i was hoping that with the meth injection i could get away with det, but i guess since i already have the meth kit ill use it for a 100 shot.....