Michael Kranefuss had been transferred from Germany to SVO in Dearborn, Michigan. Zakspeed had shipped one Ford Capri to the US. The Ford Mustang GTX was to replace the Capri in the US in the meantime, but the Ford Mustang GTP was a much more ambitious project.
The Ford Mustang had a front engine, so the GTP car was required to display the same. Bob Riley was selected to design the Ford Mustang GTP. The car was to generate as much downforce as possible.The front engine was behind the wheel centerline, which was an advantage aerodynamically speaking. A ground effect tunnel had been included between the rear wheels. Ford Aerospace would help with the design of the carbon fiber chassis. Protofab was responsible for mounting the bits to the chassis and John Mills made the bodywork. The car would be campaigned two seasons, and won its first race. But it was doomed by its engine weakness and handling problems. By the fall of 1982, Roush/Protofab began fabricating it. The chassis was made out of composites provided by Ford Aerospace. The front engine configuration allowed Bob Riley to design a car with maximum downforce. 'A clear edge of technological development' as would put it Ford Chairman Philip Caldwell. The car had been designed through CAD/CAM technologies, and Aluminium and Mylar templates were used to produce the panels. All of the chassis individual sub parts were then bonded together.
The Bob Riley creation was tested in the Ford wind tunnels by Don Kopka and his staff. The tub was made of a carbon fiber/Nomex sandwich. This choice had been made because of the carbon fiber qualities. Lighter and stronger than steel, it appeared as the perfect choice to build this car. The driver's safety was not to be forgotten as ballistic-grade Kevlar was added to critical areas to enhance it. The chassis, thus finished did not weigh more than 100 pounds. A conventional suspension was bolted to the tub. A frames were mounted at the bow, they carried alloy uprights and four piston ventilated disc brakes. Koni coil-overs and a driver-adjustable sway bar made up the balance of the front suspenders. A similar setup was mounted aft and worked in concert with a rear-mounted five-speed transaxle. At 1770lb, it was probably the most plastic intensive racecar ever built. It seemed that Zakspeed and Al Turner were not really synchronized about the way things had to be carried out, so Al Turner quit after a month. Three cars had been actually built, and one was designed to receive a Roush V8 engine. It was not to be, as literally hit the ceiling when he knew it. In fact, Jack Roush and Erich Zakowski did not have the same views, as Jack Roush intended to use his homebuilt V8s in GTP racing. But Ford did not intend to use this kind of powerplant in GTP racing, as they needed a high tech image. That's why Jack Roush left the program at the end of 1983, Michael Kranefuss was in charge of the whole thing, and he knew what he had to do. However, it seemed that Erich Zakowski did not want to work with Cosworth. It finally nailed the program. His engines were powerful, but very unreliable. High temperatures were reached within the cockpit, and it caused a driver's fatigue. The chassis also was a problem, as it was not designed by racing experts. Ford Aerospace seemed not to master some race constraints. Some major problems literally prevented from being a good racecar, but was it a conception problem? Many people were convinced that the engine configuration that had been chosen was the good one. Yet, it seemed that when the fuel tank was empty, the car was literally undrivable. In fact, many problems appeared within the course of the season, and Michael Kranefuss' final opinion about this project said it all : "It was the worst project I've ever been involved in.
The development budget was simply not up to the task. So the project was dropped at the end of 1984.