Our independent rear suspension is the for the person who needs the absolute top of the line performance and ride from his Factory Five car. The kit comes with the IRS cage, shocks, upper and lower control arms, shorter half shafts, and all hardware. If ordered with a kit we weld in all the mounts so it is ready to assemble and shipping is free, but many people have retrofitted this kit into their solid axle cars. It will work on all Mark I, II, and III cars. The center section, CV joints, hubs, brakes, and spindles are all from the extremely common late 80's to mid 90's Ford products listed below. This IRS is pin drive (54.25") width for authentic knock-off wheels that we sell..
-Factory Five Roadster, Coupe, Spyder, Challenge Racer.
1989-1997 Thunderbird Super Coupe (All Posi-traction)
1992-1997 Thunderbird V-8 models with rear disc brakes (some posi-traction)
1992-1997 Lincoln Mark VIII (All aluminum carrier, most non-posi-traction)
1989-1992 Mercury Cougar XR-7, supercharged V-6 (All posi-traction)
1993-1997 Mercury Cougar V-8 with rear disc brakes (some posi-traction), after 94 all Cougars were called XR-7’s
Non donor parts needed
Mustang Quad shocks –Aftermarket KYB shock usually interfere with tires.
½” Lug nuts (T-bird lugs are metric)
Note: Factory Five Racing does NOT approve the use of aftermarket IRS quick alignment adjusters.
Click here to download the installation instructions as a PDF.