Originally Posted by msheredy
If this were true how would they still be in business, let alone be the leader in the air filter aftermarket? I've heard complaints but have never seem proof of such claims. K&N is a stand up company.
It is true, they are in business because they have a decnt product line and good advertising, A K&N filter will make a couple more hp over a stock paper filter but I'de rather have my engine oil contaminate free.
The proof that K&N is hard on engine life has been prooven. There are many oil analysis companies out there that have documented this. If you don't believe me do an oil analysis on two different cars, one with OEM paper filters and one with high flow K&N. looking at those reusable filters you can see way more porus opening for dirt to pass through. There is a reason why we use papre filters for cabin air filtration...
http://www.bobistheoilguy.com/airfilter/airtest3.htm