My first upgrade was the RMR intake filter but i feel a loss in the power of my evo in hi rpm. I put the stock one back and the response was better. Now i install a perrin exhaust system. Do you think that rmr intake should work better with this exhaust or i should buy a k&n drop in filter for better response?

 

did the RMR include a new hard intake pipe? if so theres your problem... just use the filter itself with the stock intake pipe untill you get some fuel management... If it is just the filter then your problem is mostlikely knock, and you'll need to bump the octane up a few numbers..

 

The RMR only includes the metal base and the filter i am using the stock intake pipe. I am using 93 octane it is the hi gas in PR.

 

imo, i would just go with the k&n or hks drop drop in. they work fine. the ram air style box is adequate breathing for the Evo, until you get into the real big daddy hp #'s. i've dyno'd with the hks and a catback with some good #'s. a friend of mine dyno'd with the k&n and cat back with some good #'s also.

 

k&n drop in is awesome felt nice diference. didn't think i would with a small upgrade.