I'm in the process of buying myself a skyline, the car that i'm after produces around 220rwkw @ 18psi. The exhaust system is around 3 1/4 inches all the way through with a split dump pipe, the downer about it is that it still has the standard cat.
Would a 7ltr cat make much difference and what kind of a power increase would i be looking at?
Also looking at a UAS CAI box, could i expect much of an increase from installing one?
Thanks in advanced