K&N air filters - replacement for oems?
I've had K&Ns on my roadster since 2006 and on my A6 for the past 125k miles with zero problems. I like the fact that I can clean and re-oil them and am aware that they may/do not filter small particles as well as oem filters, and that any hp gains are negligible. But I don't drive my Crossies much and change the oil every fall, so I think that will take care of any "dirt". The real question for anybody running K&N replacements for the oem filters -- do they lean out the mix any and reduce the carbon build up on the exhaust tips?