Originally Posted by Dan_A

We tested on rolling road at college on a 2002 golf with standard air filter, then with k & n and then no air filter. The results were shocking. With k&n on was down 8bhp on standard. With no air filter down 11bhp. You are much better fitting a k&n panel filter in your standard air box unless of course you get your car REMAPPED with a k&n cone filter. Also a heat sheild is a good idea. It is the sound of a k&n that decieves people.