Originally Posted by MMME30W
I've never seen any objective data to suggest there was any measurable HP gain by using a K&N filter.
I have seen anectdotal evidence over ten years of owning a BMW of people gumming up their MAF sensor by over-oiling.
I have always used, and believe in, only genuine OEM filters for my cars.
YMMV of course. Just my 0.02.
Our car doesn't have a MAF. My 350Z did. I ran a K&N filter for 5 years. One time, I oiled the filter so much that my car left a puddle on the ground, I thought it was leaking oil! My MAF was not affected and my 350Z made great power.