The Mustang GT4 is based upon the Shelby GT350.
However the GT4 is built to be a race car, there’s nothing street legal about it. Instead of modding a Shelby GT350 to be a race car, why not built a mustang specifically for racing?
That was the idea behind the new GT4 car. The car was developed by Multimatic and Ford Performance. The car is built in Canada by Multimatic. This car was created to compete against the GT4 models of Porsche, McLaren, and Chevrolet.
The major differences between the GT4 and the Shelby GT350 are aerodynamics and weight.
The upgrades to aerodynamics are obvious with the large rear wing and splitters. The body is completely covered in carbon fiber. Since the car isn’t built to be street legal, the cabin of the car includes only what’s necessary to be FIA compliant – roll cage, MOTEC data system, Sparco racing seat, and a racing harness.