[aerohead]

while there is much hype about aftermarket air filters,there is no laboratory evidence to confirm advertized claims.K&N was tested against factory micronic paper element filters and found to filter less effectively,foul the soonest.Don't know about "fabric" filters.Air filters are a dead end with respect to improving mpg.They provide virtually no restriction to the intake flow,and consequently have no effect on volumetric efficiency of the engine,even at wide open throttle.There surface area is carefully computed to do exactly this.Spend your money elsewhere.