If I use a Stock STI 2.5L block, I need to know which pistons will give me a CR of 8.5:1, using machined heads and OEM STI head gaskets? Also need to know how much I should machine down the stock heads with this combo. Vendors, if you have something that will work for me, chime in. I'd like to avoid using a crometic head gasket if at all possible for timing purposes. Thanks, JC

Alternatively, I'll buy just buy a fully built block if you'll take my brand new STI block plus some money in exchange for the built block.

Cheers, JC

EDIT: IS anyone using these pistons? http://www.techworkseng.com/Products/Subaru_Forged_Pistons.htm
These are guys are in my city and just wondering what the thoughts are on these?

i would call up some vendors along the lines of Crawford... They I am sure will know what pistons you need to achieve your desired CR...I am guessing they might even have some as well...

What about Cobb pistons? They claim 8.5:1 with their short block. Could I just drop some of their pistons in? Not sure what head gasket they use though...

i honestly would call them up and get the info straight from the horse's mouth so to speak...

I have talked to them all and kinda got my answers. I think I can pretty much get whatever I want made to spec.

We use special order JE pistons to get 8.3 to 1 in hybrids with stock sti head gasket thickness, since wrx combustion chamber is smaller than sti chamber and the bore and stroke is different, which all changes comp. ratio.
Thanks, Tomi

We use special order JE pistons to get 8.3 to 1 in hybrids with stock sti head gasket thickness, since wrx combustion chamber is smaller than sti chamber and the bore and stroke is different, which all changes comp. ratio.
Thanks, Tomi

I was shooting for something between 8.3 and 8.5:1. I think that's a good compromise between off-boost performance, ability to handle a bigger turbo (boost) and reliability on pump gas. I certainly want to keep my quench height to less than 1mm though. Can you PM me a price on some pistons that will achieve this? Will I need wrist pins, etc.?

PM sent.

call cobb they have pistons specificaly designed for what u want. i have them in my car and they seem to be working really well