Originally Posted by Ape Factory

Nismo R-Tune intake, just do some hunting around for a good price. No cutting, has bypass valves that prevent hydrolock and is extremely well-made. If you plan on having the car tuned, I'd go that route. Has venturi inserts to play nice with the stock tune that you can remove for tuning.

Otherwise, any of the kits that run the filters behind the front grille are a good alternative. You'll see gains with the Stillens without tuning due to the way they've designed the tubes surrounding the MAF's.