Turning A 2000 Mustang GT Into A Track Weapon With An IRS Swap

Back in the day, removing the factory independent rear suspension in favor of a solid axle was the move for drag racers with Cobras. However, for those who want to carve corners, an IRS has its merits. The factory rearend loves to float around, struggling to keep the tires planted on rough pavement. To cure that ailment, Nathan Anderson brought his project car to Late Model Restoration’s shop for an IRS swap.

Hunting down hardware started with pulling a neglected cradle from a wrecked ’99 SVT Cobra. The crew stripped the dirty assembly to bare metal, laying down a fresh powder coat. Slipping a Full Tilt Boogie kit into the mix traded the soft factory rubber for rigid Delrin and solid UMHW bushings. “I would highly recommend replacing all the bushings with a solid style bushing,” Anderson advised. Beefing up the center section with a Torsen differential also gave the driveline the strength to survive hot laps.

Unbolting the live axle opened up room to wrestle the aluminum cradle into position. Pushing the assembly into the chassis required removing the factory pinion snubber and widening the front torque boxes. Working underneath, mechanics carefully bent the hard brake lines to keep the control arms from pinching the fluid tubes. Wrapping up this IRS swap also forced the team to find a shorter driveshaft. Connecting the drivetrain went smoothly, right until the offset mufflers smashed into the new subframe, requiring a temporarily dumped exhaust.

Firing up the SVT Cobra for a quick test drive proved the hard work was worth the effort. The back end stopped dancing over bumps, gripping the asphalt with total confidence. “The car feels a lot more planted,” Anderson explained. Rolling the Mustang onto the shop scales settled a stubborn debate about the added bulk. Checking the numbers confirmed the independent rearend only tacked on about 80 extra pounds.

Building a believable ’00 Cobra R clone requires more than slapping on a fiberglass hood and a V6 bumper. Chasing genuine cornering performance demands a fully independent rear suspension. Finishing up this IRS swap finally arms this Mustang with the exact mechanical grip it needs to attack weekend track days.