I haveto agree with the above. I used the drop in and it yielded no performance gain, neither any MPG gain.

The filter got dirty so before I could clean it I popped the old (yet still clean) regular filter that I had. I drove that way for some time completely forgetting that I took the K&N out and was driving with the regular filter. Made no difference. I have a Flowmaster 40 Original on the back as well with 2.50 pipes.

Icleaned the K&N and sold it. It was not worth the money that I spent. I know that the whole kit might yield better results but not much better. I don't think that 1-2 HP would be worth the damn $180. I'd rather buy a BL to better clear my tires because them suckers still rub at full compression!