that's totally wrong. u will get better MPG with a less restrictive intake system. will u really notice the gains? not really. it's only about a 10% (more or less dependin on the car and it's mods) mileage increase, per gallon. intake, header(s), and exhaust systems are just simple bolt-on's that replace the factory's very restrictive systems. it isn't like addin a blower or somethin, where u'd have to have a much more aggressive fuel map. i have changed out the factory intake system in every car i've ever owned. i will probably follow this trend with all of my future cars as well. i've had the most basic set ups like a short ram intake to a more aggressive set up with a velocity stack and custom piping. the benefits from havin an aftermarket intake system really outweighs the bad stuff. the only real negative, to me, is the oh so $exy sounds that a simple intake system can bring out of yur car. it makes me want to floor the damn thing everywhere i go! u will also notice broader low and mid-range power.