K & N Filters 77-2514KP 97-03 FORD F150 4.6/5.4L Estimated horsepower gain of 9.7 HP at 4093 RPM Designed to improve throttle response and engine sound Easy to install, usually in 90 minutes or less Replaces entire factory air intake system Lasts up to 100,000 miles before service is required (depending on driving conditions)