09 TSX Tech Package. I'm planning to replace my OEM Engine filter for a K&N filter. Do they really increase horsepower and gas mileage or is it better to keep using the stock filters?? Thanks for your comments!!

 

There isn't an application for it yet. Some will tell you not to run them on cars with MAF's like ours. As long as you don't over-oil it & spray your MAF regularly with MAF cleaner (ONLY) IMHO, you'll be fine and they do work, although not as good as a CAI. There's a CAI thread on here somewhere.

 

see: http://www.toyota-4runner.org/showth...threadid=14801

 

Do not use a K&Crap filter. I've been a tech for over 24 years and have seen the damage these filters have done first hand. The only way you will see ANY benefit in powwer gain, is if you drive bouncing off the rev limiter all the time. Oh yeah,good luck on collecting on any warrenty clowns offer.