[P.S.]

I run air filters on every car that I care about. Have never experienced the richening condition that Fordbarn preaches as fact. If the air filter starts to get clogged, then it will begin to run a little fat, but you can tell, and you know it's time to clean the air filter. Then when you do, notice all the dirt and crud that comes off and thank yourself that it wasn't ingested by your motor.