i'll tell you that ive never ran a dyno on my car but what i do know is the HP that everyone brags about and claims varied based on mods and motors. i mean think about it......5-10hp for an air filter. why dont the manufacturers just use it then? what do you get if you put one in a 3 cylinder geo? key words are up to. the better companies out there use % instead of set HP #'s. ive had cars that i put a filter in the stock box and thought i felt a difference but its all in your head. now if you open up your intake and exhaust then you'll start to see those #'s. i would recommend the k&n setup though b/c you can keep it forever and cleaner kits are cheaper thank replacing your air filter every x amount of miles. i like mine. id take it over a generic or replacement filter any day!!! dont know if this helps but just my opinion.
