Originally Posted by banzai
I have a 2.5L swap, WRX heads with helix 264 cams. the heads were ported and polished a bit, the chambers cc'd out to 51-ish. with STi head gaskets that gave me about 9.1:1 compression.
on a VF22, with 50/50 alky injection, i had 15 lbs of boost at 3K, AND 300 ft/lbs at the same point.
i had 300+ ft/lbs to about 5700, and then it started to taper off. peak tq was 340.
peak boost was about 17.5 lbs on that dyno session, on the road it was 18.5 or so.
after another two weeks of tuning, the car kept getting better and better, i think it was probably running around 360ish ft/lbs or so, and it pulled like a beast in every gear. even fifth.
that is all the data that i am goign to ever get on that setup, i am goign a different route.
i would highly reccomend the helix cams if you're looking for a lot of midrange and a big broad tq curve.
also keep in mind that you're goign to want a small ish turbo, like a VF22, big 16G or maybe and 18G to help you build boost fast.
A turbo will help you ALOT..
8cm2 18G should provide enough airflow for a flat tourqe curve to 6500+ rpm's then slowly start to taper.
STI chamber should measure out to 52cc's, so your wrx heads have about 6cc's worth of volume taken out of them.
What "static" compression are your pistons designed for, and for what heads?
.. Or are they stock STI pistons?