As the GT3 homologation deadline for the 2024 racing season draws near, General Motors and Pratt Miller Engineering are working feverishly to finalize details of the Corvette Z06 GT3.R that will compete, at a minimum, in the IMSA WeatherTech SportsCar Championship and FIA World Endurance Championship next year. Wind tunnel and dyno testing is scheduled to begin in the weeks after Le Mans, and full homologation is expected by October. But there are many things to be discovered before then, and even after.
“It was definitely a benefit that we started our development so early; we were on track last fall,” explains Corvette Z06 GT3.R Program Manager Christie Bagne. “So by the time we hit the end of last year, we already knew the primary aero concept that we’d be moving forward with and things like that. Then we were able to move on very quickly onto things like different damper evaluation. So we’re at the point where we’re working on the fine tuning, and that was definitely enabled by starting that development process last fall.”
The engineering team has been primarily testing on the tire it knows — the same Michelin tire it races on in the WeatherTech Championship. But before and after homologation, they’ll be working to gather as much information as they can on how the car works on different tires so they can have the information for customers racing in different series around the world
“We’re sourcing Goodyear and Pirelli and making sure that that’s worked into our development testing plan as well,” says Bagne. “We want to get well ahead of it in terms of testing different tires, testing different configurations for different series. We’ve developed a great platform with this car, where the current car was developed very much to run on a Michelin tire at IMSA tracks and Le Mans primarily, the GT3 car has been optimized for a wider operating window. So we expect to have quite a bit of success in terms of being able to have the workability to come up with the best possible setups for the different tires, and then provide those learnings to our customer at the onset, so that when they hit the grid with their car, they’ve already benefited from all the testing that we’ve done in advance.”
The priority will be having cars ready for IMSA and WEC competition next season. But while GM wants to have cars for customers to race worldwide, including major GT endurance races such as the 24 Hours of Spa and the 24 Hours of Nurburgring — where Bagne and the key members of the engineering team spent last weekend getting the lay of the land — the aim is not to turn out a huge volume of Z06 GT3.Rs. GM will build at least 20, but it doesn’t plan to churn out hundreds of GT3 cars like some other manufacturers. Because of that, the manufacturer expects to be able to deliver a better customer support experience with their partner PME, Bagne notes.
“We realize that this is our first time launching a proper global customer racing program with the Corvette. So because we’re low volume, and we intend to have the support be a differentiator, the customers will have world-class access to us as the manufacturer representatives, but then also the technical engineering support.
“They’re going to have support at the races, but also in between the races, which arguably matters even more than just having someone firefighting at the races. They’re always going to know exactly who to call — we’re going to be in constant contact with our customers, understanding what their needs are, how we can support them, how we can help them win races … that will be a differentiator. Every individual that’s racing these Corvettes is going to be treated as an individual with individual needs. We’re going to be listening to their feedback, and they’re actually going to have a voice in what we do.”
While this may be GM’s first true GT3 car — previous Corvette GT3 cars were built by Callaway, and Cadillac’s ATS-V GT3 was never sold to customers — they don’t seem behind the curve compared to other manufacturers that have done several iterations of homologated race cars, although only the heat of competition will truly reveal if that’s correct. Part of that is because GM and PME have previous experience with homologated cars in the GTE/GTLM versions of the Corvette, now on its fourth generation. Another factor is that some of the key personnel, such as engineer Kyle Millay and PME technical director Ben Johnson, have been on the pit stand at Daytona and Le Mans. The Z06 GT3.R is a race car designed by a race team. The experience earned through years of racing Corvettes are going into the GT3 car.
It also doesn’t hurt that GM has vast resources in one location. GM Powertrain in Pontiac, Mich., is 40 minutes away from PME. And PME is 20 minutes away form GM’s Milford Proving Ground. They want to test something they’ve implemented on the car? No need to book time at a track hours away.
“[A couple of weeks ago] we were able to shake down a chassis at the Milford Proving Ground. So we’ve now had two tests using our own road course, which is a great opportunity to get the cars on a transporter, drive 20 minutes down the road, have two full days open on a racetrack, work on all kinds of drivability items — pulling out of the pits, things like that. We don’t have to wait and book a test day and try to get track time to work on that stuff. We just cruise right over to our proving ground and enjoy having that in-house capability. So again, there’s so much efficiency that I think is going to result in a better car,” says Bagne.
A little farther afield, the program will also benefit from the Charlotte Technical Center. In fact, Bagne credits the WEC team’s success at Portimao, a track where Corvette had never raced, with the Driver-in-the-Loop simulator and other work done in Charlotte.
Whether the experience and efficiency all comes together in success for the first Corvette GT3 will be seen at Daytona in January. But Bagne and her team certainly seem to believe they’re on the right track to produce a winning car.