K&N 69-3521TP Typhoon Air Intake Kit, Short Ram, Polished Estimated horsepower gain of 6.84 HP at 4600 RPM Designed to improve throttle response and engine sound Easy to install, usually in 90 minutes or less. Filter Large End Diameter 7.5 in (191 mm) Replaces entire factory air intake system Lasts up to 100,000 miles before service is required (depending on driving conditions)