get the intake/header/exhaust combo. The new K24 love mods.

Injen RD Intake is good (I personally have one)
AEM CAI or AEM V2
DC Sport 4-2-1 header (stainless/ceramic) difference is marginal
GReddy EVO / EVO 2 exhaust (EVO 2 is completely stainless)

Go for it man and happy modding.