I have a 2002 WRX with a load of mods (327awhp).
2.2 Liter Bored WRX motor
Grimmspeed Uppipe w/38mm EWG
Full 3" TBE
APS Turbo inlet house
and a bunch of over stuff but those are the relevant ones here.
I drove me friends '07 STi and loved how it just gets up and goes. Torquey all through the rev band especially down low from idle. My WRX however, off the line without launching it my car doesn't get going till 4.5K RPMs. It is a slug in turbo lag. I was wondering was gives the STi that "GO" characteristic. Is it the gearing in the transmission? Is it the AVCS heads? Is it the 2.5L short block? Is it all of those? If I wanted my car to respond better what mod would be best? Is AVCS going to make a big or rather noticeable difference?