AirRaid Intake Systems increases air flow by 20% !! Provides up to 15hp! Mac Products Air Induction System Bolt on 15-20hp to your Ford Truck! F-Series/Expedition SuperDuty/Excursion Lightning K&N FIPK is designed  increase horsepower and acceleration by replacing the restrictive factory air intake assembly with a K&N high flow element and necessary components. K&N Air Intakes Call or email for prices & ordering information.