Pablos said: "I don't like the K&N because it allows too much dirt to pass. I used to have a link to a Toyota group which did a study the K&N vs. paper, and quite a large amount of dirt and grit got through the filter. I wouldn't use one on a normal street car even if I wasn't an Amsoil dealer."

Really? That is definitely a new one to me. I would really like to see your link, or any other study done by an unbiased party that proves the K&N air filters allow "quite a large amount of dirt and grit" to pass through to the engine. My wife and I have put well over 300,000 miles on several different vehicles all equipped with K&N air filters. Never had any problems or saw any signs that the K&N filters allowed "dirt and grit" to pass through. I've used them on street cars and race cars. No problems whatsoever. If you can find any studies by unbiased 3rd parties, I'd like to see them.

-Keith