Ok so a few weeks ago I was on my way home from atlanta varsity meet and my car started over heating... long story short, my head gasket is GONZO! So now I have to choose what gasket to go back with. I've heard a lot of different opinions and haven't seen what I'm looking for yet... basically my engine already has FULL BC head, CP pistons 11:1, stock rods, acl bearings, arp head studs, steele sleeved, and block is bored :50 over. I was originally using an OEM head gasket on this setup but what do you guys think I should go back with? Or should I just rip out the pistons and go 9.5:1 or something??? I've been hearing a lot of bad things bout thick head gaskets blowing out so idk bout them...

 

u dont sleeve a block and then run a thicker HG. stock HG will be fine. maybe 10:1 pistons but i dont think its a big deal at all. just pop in a new HG and make sure the overheating problem is taken care of.

 

Well the over heating turned out to be due to the blown HG blowing all the coolant out of the radiator... sucks.

 

so you built the motor for boost and stuck with a compression ratio that high??
What size turbo are you running and what kind of boost are you at?
Get a stock hg and drive that thing down to topspeed and get tuned.

 

actually i was building the engine for use as n/a with nitrous.... but then i got a deal on a turbo kit and went FI. im using a t3/t4 manifold with pfab log manifold. and im running 12lbs of boost. the only problem is im not totally sure if the oem head gasket is ok for a .50 over bore? im wondering if thats where my problem came up. if i had originally planned for FI then i prob would have gone ahead and gone with lower compression pistons..... but....

 

you'd have to measure the bore on the stock gasket.. you do not want the gasket to be smaller than the bore.. especially on these motors. the piston will hit the hg if its smaller than the bore.

 

I thought at some point I saw something about a good head gasket that was for larger bored s2k's with turbo app... but I can't remember where I saw it and haven't found it searching yet

 

Cometic makes whatever size you want

I'm pretty sure a stock gasket is big enough for 0.5mm oversize

Just measure the old one to see.

 

ok. well ill just recheck the head gasket when i pull the head. i am just wondering why this new gasket with less than 10k miles blew out on me. the entire engine has less than 10k miles... ill just have to see what the deal is. idk if i wanna go buy lower compression pistons while i got it torn down or not tho.... havent decided. any input? i know alot of guys on here are running good power out of 11 CR and since everthing in mine is built like a tank... i assume it will still hold up well under pressure. im wondering if maybe the head bolts werent torqued well enough. just thinking.

 

detonation probably

how much power was it making?