1999 Mustang Two-Valve Bolt-Ons - Preparation HP

An E8 inverted Torx socket was needed for the ABS sensor, along with great care, as the rusty stock unit tends to break upon removal.

The steering rack requires 15mm and 18mm sockets and must also be properly secured via bungee cords or zip ties before reinstallation.

A 15mm socket was used to disengage the sway bar, the springs were removed, and the K-member was unbolted at the motor mounts with a 7/8-inch socket with support from a jack.

With the K-member out of the way, the EGR (1 1/16 inches) and oil dipstick (13 mm) were removed prior to the stock manifolds.

The steering shaft was unbolted from the interior with a 10mm socket before being threaded through the middle of the driver-side header.

Since Gangsta would need all the help it could get to motivate the little 4.6, we went with Kooks Custom Headers 1 5/8-inch stainless steel long-tube headers and x pipe system with high-flow cats. These are easily one of the best headers on the market for modulars because of the high-quality bends, welds, fitment, minimal loss of ground clearance, and NASCAR-style 2½-inch velocity spike collectors.

In order to shoehorn these headers into the SN-95's tight engine compartment, Kooks designed the top primary to be unbolted via an 11mm socket. This gives the headers enough play to maneuver around the starter. Open-ended bolt holes on the flange also allow the headers to slide onto the provided 13mm bolts and sandwich the supplied gaskets.

The high-flow cats and collector connect with a ball-and-socket junction (instead of straight flanges) and two 9/16-inch bolts to prevent exhaust leaks.

The X pipe system, as well as the after-cat, have several different band clamps to secure them instead of being welded up as one piece, which allows quite a bit of adjustability (a definite plus). Unfortunately, it also takes quite a bit of maneuvering to get things just right.

MRT's Max Thunder after-cat is made up of 409 stainless steel, mandrel-bent, 2½-inch tubes, chambered mufflers, and its signature brushed- stainless tips (chrome tips are also available). This classic combination promises years of durability and a deep, musclecar growl.

With a 14 and 15mm socket, the entire exhaust system can be assembled. It's best to leave the bolts loose until everything is lined up straight and the pipes are tucked as close to the floorpan as possible. A jack is helpful to hold the mufflers and pipes in place.