4.6L, 5.4 liter V8 1997-2003 F-150 Designed from scratch for the Ford 4.6 and 5.4 litre. From our own Engine Breather Boot to our MAF adapter with a custom venturi for increased air flow. This kit does not get any better. Dyno tested at 17.9 horsepower plus 29 lbs. of torque.