HKS makes a head gasket thats 1.6 mm thick and its suppose to lower compression to 8.3.1. is there anything i should know before buying this head gasket for $230. Will there be any bad affects from lowering my compression so much. I have a 98 GST.

whats the reason behind lowering the compression? i always thought that the higher the compression the better

With lower compression you can generally run more boost. If you have stock boost and lower compression, you will make less power.

I wouldn't recommend the HKS being so expensive, where the Mitsu MLS is like ~70 bucks at I think partznet.com and stock gasket is like ~79 from Mitsu. Are you considering ARP head bolts too?

the only reason i wannted the HKS(disreguarding price) is because it lowered my compression so much. How much does the one your talking about lower compression. Yes i do plan on getting ARP head bolts.

Can a head gasket really lower the compression?
I never knew that.

yes it can

my exhaust is white so im either guessing that im leaking coolant from the turbo or the headgasket. Has anyone ever had this problem before, and if so what was the problem from.

well ifigured it out that it wasnt my head gasket, my turbo blew up today, thatzs what the white smoke that was comming out of my exhaust was. I got the head gasket anyways though, and im getting ready to install my evo turbo on wednesday. thanx guys.

Lowering your compression ratio from 8.5 to 8.3 will have no noticeable effect... ;) Certainly no worth the money HK$ charges. Iwould takes Joes advice and run the mitsu metal gasket, its about 90 buks though from most places. The stocker has been good to over 500 hp (chads car for example) but I have had great luck with the metal one, even after reusing it :D

i thought the compression on the 2g was 9:1

i though eclipse was 8.5:1

2G is 8.5:1

isnt the 1g 8:1?

Does the aftermarket head gasket simply lower compression by creating a longer area to compress...i.e. more room for air fuel mixture to survive while being compressed?

It would seem that way. Thicker gasket, lower compression.

hey kevin... i didnt know you can reuses the metal headgaskets, how many times can you reuse them? thats a very handy piece of information!

I reused it once with no trouble, but a third time wouldnt have been pretty, it was beat up. The rubber around the cylinders had deteriorated.

1g is 7.8:1, 2g is 8.5:1

And yes, the CR drops with a thicker gasket because there is more room for the air when the piston is up. Displacement is the same, so the air pulled in is the same. But more space means its less compressed.