Same thing goes for the K&N as the wizair to a point; just because its a big name brand with lots of advertising, doesn't mean its the best.

The K&N box only has the sides and bottom- the top is open (an attempt to make it easier to install and change the filter). They try to seal the open edges to the hood and such with a rubber strip, but its not great. Doesn't matter if its hot outside or not- the radiator fan wash is blowing over a 200* radiator, and your exhaust crossover pipe is a couple inches away and a few hundred degrees as well- so its always hot under the hood. By beefing up the insulating strip and making it better follow the body, we cut over 10*F off the IATs on my buddy's K&N intake on his GTO.

The wizair seals the top off with a solid piece, so the only rubber sealing surface is in the corner by the headlight and fender, and its a little tighter fit there. The wizair also has more insulation on the box, for less heak leakage through the walls.


I don't see why they would sound that much different, the wizair usually comes with a K&N filter- so its still a big K&N cone on an intake tube, only difference is the box its in; I guess the wizair is a pinch quieter, but not by much. Only thing louder than those two is an open cone in the engine bay.