Our premium rear suspension delivers the best ride comfort AND the best performance. This suspension is available to be used in the Mk4 Roadster, 289 USRRC Replica, Type 65 Coupe, and ’33 Hot Rod. The IRS can also be installed in the Mk4 Challenge Car. NASA-Factory Challenge Series class requires the 3-link rear suspension, but the IRS is legal in all other classes.

The suspension package includes: welded tubular steel IRS frame, upper and lower control arms with bushings, grease fittings, and fasteners (powder-coated gloss black), left and right IRS toe adjustment arms with rod ends and fasteners (powder-coated gloss black), KONI coil-over shocks with coil-over kit, springs, and fasteners , right and left CV axles, rear wheel studs, IRS e-brake cable adapter, differential mounting components, bushings, and fasteners, driveshaft adapter for manual cast iron center section.

The IRS assembly requires: 2015 Ford Mustang manual transmission center section, Ford brakes and spindles (also available from Factory Five Racing).

Note: Standard IRS shocks and brakes shown on driver’s side (red body KONI shocks and silver brake calipers and rotor). Optional parts on passenger side include silver-body KONI double-adjustable shocks and optional Wilwood brakes (red calipers and black rotors).