You guys should really do some searching on the internet for air filter testing . I spent 3 hours reading through lab and real world testing . Some of the test results were shocking. One thing is for sure not all air filters are created equally. I found tests where an aftermarket paper filter actually flowed better with higher efficiency than foam or cotton gause types. Many of the lab tests showed that most filters offer about the same restriction to airflow. The major differences were capacity. This is where the gause type (K@N) really suffered.

In my experience the biggest problem with K@N filters were wet muddy conditions . The cotton would get wet and swell severly restricting airflow. Running with the airbox lid off was a huge mistake to. I think they would be fine for sand duning but for very dusty or wet conditions your best bet would be a 2 stage foam.

 

Thanks! Going looking tomorrow. Been running them for years on my other motors. No need in trying to save this one. LOL!

 

Seems like a lot of people think K&N's are great. Have you ever seen a good dyno from a reliable source that shows a k&n giving a quad more horepower? I haven't yet, but would love to see one.

 

No! None on ATVs. I've done several on cars but, fractionally speaking, it would be hard to measure that small of an increase on a 10 h.p. motor when we only get 3 to 5 on 300 to 750 h.p. motors. Our 750 and 550 horse motors have blowers so I don't know what effect has either. I don't know of any place locally that can dyno a quad. I guess I could ratio down a 3 h.p. gain on a 300 h. motor but I doubt that would be accurate.????????

 

WISTECH could you tell me what brand paper filter outflowed the K&N and foam type filters? Maybe a link? Thanks for the info.

 

Check out Frankencar performance. They have some interesting info on the apexi air filters. They are a dry type filter than looks similar to the k@n but has air funnels built into them. Apparently they have far superior filtering abilty over all others and flow higher than even K@N.