America's best selling pickup got revamped for 2004... and MagnaFlow ponied up with two new systems for the F-150 in both single and dual exit configurations. Similar in design to our previous generation F-150, most of our F-150 cat-back performance exhaust systems feature high flowing, 3" mandrel-bent, 100% stainless steel piping and straight-through, wide open performance mufflers. The Supercharged 5.4L engine produced 25 hp and 30 lb,-ft of torque with our system.