Charon wrote on 04/21/10 at 09:35:09:Perhaps I am a little cynical, but I would point out that K&N wouldn't sell many filters if they didn't advertise better airflow and more power. They also advertise how long the filters last, but don't mention the mess of cleaning them. It is also said (but not by K&N) that the extra air flow comes at the expense of poorer filtration, especially of smaller particles such as airborne dust.
Its the closest thing to an oil bath air cleaner without getting one. Ever wonder why oiling an air clearn element came about?? Dry guaze and paper filters olny get so much. To fix this, the use of a pre filter was adopted. Helped , but still needed improvement. Then someone decided to oil the foam on the prefilter. Hmmm, works well, but still restricted air flow. Ditched the paper and desined a pleated filter that will trap oil and allow the most airflow without losing the oil into the motor.
They only make a mess when you over oil them or squish them in the filter box. Cleaning is very easy, drop it in a bucket of hot soapy watr and shake it around, let it air dry or take the compressor to it. You could hit it with a preassure washer, you can hit it with carb cleaner. You can clean it in the solvent tank. Dishwashers work great. Re oiling isn't that difficult as long as you read the dirctions and 'spin' it after a few minutes to let it run. By spin I mean shaking the excess out, if any. All my K&N filters are round, so thats why I spin mine. I have had it on the dyno with and without K&N filters and they work, period.