I don't know I hear a lot of people say you get like 1 extra horse power but who is going to notice that, but since a regular one is about 20 when the original one needs to be replaced im going to get a K&N because everyone seems to think they are better whether they improve power or not. $34 including shipping on amazon.Everybody seems to upgrade their air filters to K&N, but at £40...is it worth it?
Does it really make much difference?