I ran the K&N FIPK for about 70,000 miles, then went back to the original airbox with an Amsoil filter. My mileage went up 1-2 miles per gallon depending on season and there was no noticeable decrease in performance. Food for thought. You really can't make the intakes any more efficient than they are from the factory because they're designed to work with the engine to attain the best possible gas mileage. Subsequently, you're going to get pretty much the best performance out of it as well, barring any major changes to the internal components of the engine.
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2003 Renegade 4X4 5-Speed, Bright Silver *TRADED for 2013 Wrangler*
PIAA 520 Auxiliary Lights
Garmin GPSMAP 76S
DynoMax Ultra Flow SS Muffler
Amsoil Ea "Absolute Efficiency" Air FilterNokian Vatiiva 235/70/R16 Tires
Pixeldzn's "RENEGADE" decals
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