A good cold air induction kit will cost you around 350 and "maybe" give you a few bhp. Group N rally cars use the standard airbox and only the S204 has a different air box. Basically the standard airbox on the newage cars is very efficient anyway.
why not get a remap for a little over twice that for some real proven bhp?
If you have to have on then the K&N 57i and sti trumpet or the APS cold air induction kits are the ones to go for in terms of maf safety and actually increasing bhp. Quite a few of these induction kits actually reduce bhp and some that increase bhp reduce the torque figures. They do sound great though but in terms of power gains they have been proven time and again to be of little use.
Frawls
