When Ford CEO Jim Farley decided to create a street car for the Mustang GT3, the project was kept under wraps. A secretive skunkworks group was formed in closed-door meetings with non-disclosure agreements in place. The idea for the Mustang GTD progressed to an undisclosed aluminum warehouse and was quietly taken to Multimatic, a leading company for GT3 and GTD work. The public only became aware of the GTD much later, when a video of factory driver Joey Hand testing a Mustang GT3 race car at Sebring was posted by Jim Farley on X (formerly known as Twitter) on March 21, 2023. In response, Farley asked, “Should we make a way?” By that time, GTD had already started to develop without public knowledge. Seeking to learn more about GTD, we accepted Ford’s invitation to visit the Multimatic facility in Charlotte, North Carolina, where Mustang GT3 race cars are built, and then witnessed their performance at the Rolex 24 at Daytona.
Jamey Price | Car and DriverWe asked Mark Rushbrook, global director of Ford Performance Motorsports, why Ford has devoted time, money, and effort to both projects. His response was straightforward: with Mustang sales increasing in Europe and the 60th anniversary of the name approaching, Ford aims to connect with fans globally by having Mustangs racing on tracks worldwide every weekend and competing in GT3 for the first time since GT was withdrawn after the 2019 season. As for GTD, it’s Jim Farley’s vision. Production Roots The Mustang GT3 starts its life on the production line. The racing car is based on the Dark Horse car, and Holt and his team at Multimatic utilize insights from the GT3 car to adapt it to the road-going GTD. “From road to race, I’m chasing the road,” said Rushbrook. The similarities between the two cars are evident, from the larger front fenders to the twin hood vents to the gooseneck wings on the rear of the cars. 
Jack Fitzgerald | Car and DriverLarry Holt of Multimatic. Despite the regulations restricting some of the technology of the GT3 car, Multimatic implements features like the drag reduction system (DRS) on the rear wing to optimize the GTD in ways different from the competition car. “Everything on this car has a function,” said Holt, referring to the GTD. Data from the GT3 wind test is directly utilized in the GTD, with details such as data on the louvers on the front wheels being shared between groups. According to Holt, this data contributes to removing about 200 pounds from the car. The GTD, like the race car, generates 1500 to 2000 pounds of downforce at 150 mph. Additionally, the GTD adjusts its frontal force when the DRS brake is activated to prevent the center of pressure from moving around the car. Every String at Work With the hood removed and the “Ford Performance” lettering above the engine, it’s not obvious that the pickup truck shares the same origins. However, like any other GT3 engine, the Mustang’s naturally aspirated 5.4-liter V-8 starts its life on the production line. While the GT3’s power remains close to 550 hp due to power regulations, the GTD does not adhere to the same rules and features the Mustang Shelby GT500’s supercharged 5.2-liter V-8 tuned to 800 hp. In GTD, a dry-sump fuel system and a donut-shaped gearbox replace the production car’s 10-speed automatic transmission. As the competition car does not need to follow the same safety rules as normal street cars, Multimatic positions the 5.4-liter V-8 low down and far back in the engine bay, wrapping the firewall around the engine to offset the nose weight created by the front-mounted V-8. Both cars utilize a transaxle behind a traditional trunk and an exhaust cooler fed by air and two scoops in front of the trunk. Air from the transmission cooler exits through the vents between the taillights. Development on both cars continues, even after the GT3 car has begun racing. We spoke with Rushbrook about the progress 18 hours into the Rolex 24. While facing challenges such as tire debris, Rushbrook expressed that the issues faced are far less compared to those experienced with the 2016 GT. Despite finishing sixth and ninth in class at Daytona, there are many races remaining for the Ford Performance Mustang GT3 to overcome challenges, and there are still months of development ahead for Ford and Multimatic to refine GTD. Gremlins or not, we eagerly await GTD like a child counting down the days until Christmas. Jack Fitzgerald’s love for cars stemmed from his passion for Formula 1. After a brief sales stint in college, he established a car dealership to manage the new cars he couldn’t afford. His journey led him to Car and Driver after scouring Wisconsin for automotive news, and he now aims to prolong the lifespan of his 2010 Volkswagen Golf.
