Hey guys as a soon to be new jeep owner I'd like to know what mods I should get, if any, over stock. I see many here are getting the K&N filters etc. Ever notice any actual difference? Don't the K&Ns let a lot more dirt into the engine? I don't want to have to spend a lot or go some place to have a professional install something. Just looking for a few alterations that might increase the MPG while on a field trip.