GTP Homologation Is the Race within the Race

By John Oreovicz

IMSA Wire Service

DAYTONA BEACH, Fla. – It’s no secret that the four participating manufacturers in the new Grand Touring Prototype (GTP) class of the IMSA WeatherTech SportsCar Championship have been testing and developing their 2023 LMDh challengers, literally around the clock.


But there is another race unfolding behind the scenes as Acura, BMW, Cadillac and Porsche work with IMSA and the Automobile Club de l’Ouest (ACO, the organizers of the FIA World Endurance Championship and 24 Hours of Le Mans) to get their cars officially homologated for the upcoming season and beyond.


Matt Kurdock, IMSA Technical Director, is overseeing the comprehensive, time-consuming process for the WeatherTech Championship that will lock in the design of the competing cars for the next five seasons.


“Homologation is a process capturing the specification of a lot of detail in the car, the engine and other aspects of the vehicle,” Kurdock explained. “The idea behind it is that it’s a way of controlling costs and making sure that the specification of the car is frozen.


“A homologation formula allows the manufacturers some freedom on what they want to do, but it allows us to make sure that all examples of the car are presented the same way if there are multiple teams among the same manufacturer.”


The goal of LMDh homologation is for the participating manufacturers to receive final technical approval soon for the cars they will field when sports car racing’s worldwide 2023 calendar kicks off at Daytona International Speedway with IMSA’s Roar Before the Rolex 24 testing from Jan. 20-22, followed by the Rolex 24 At Daytona from Jan. 26-29.


Ideally, all four manufacturers will receive certification in the next few weeks, prior to an IMSA-sanctioned test at Daytona on Dec. 6-7 that will serve as a final dress rehearsal for manufacturers, teams and IMSA itself before competition starts in anger in January.


“We are in the process to homologate the Porsche 963 for IMSA but also for the FIA WEC championship,” said Urs Kualte, Director, Factory Racing LMDh for Porsche Motorsport. “As this is a complex process, it takes some time, but we are very confident to finish it in time.”


Communication Has Been Key


Indeed, homologation is a lengthy process. It started with manufacturers presenting to IMSA and the ACO proposals for the powertrain and styling of their cars, along with CAD (computer-aided design) models. As the cars were developed, both conceptually and physically, there was frequent communication between the manufacturers and sanctioning organizations to clarify questions about potential legality.


“There’s a lot of back and forth,” remarked Mark Crawford, Large Project Leader for California-based Honda Performance Development (HPD) in charge of the Acura ARX-06 program.


“We work with IMSA to get the car where they’re happy for us to go racing with it, and then we go back to the teams and make sure that they understand the form of the car they are supposed to bring to race in January. It’s a bit freeform in the process, but we understand what it takes to communicate back and forth and get on the same page if we have to change a part for any reason, whether it’s to make it more durable or make it cheaper.”


The final step in the homologation process will unfold over the next few weeks. Each manufacturer will deliver an actual car to IMSA and the ACO, which will be tested at the full-scale, rolling road Windshear wind tunnel in North Carolina to see if it meets the LMDh formula’s strict aerodynamic guidelines. Inspectors will then fully disassemble the cars at the nearby NASCAR R&D Center to ensure compliance with homologation documentation previously submitted.


“Certainly, IMSA and the ACO’s target is to have cars as much in the final specification as possible for the upcoming Dec. 6-7 test at Daytona,” Kurdock said. “I’m sure the development has been very taxing for all involved, our suppliers, manufacturers and constructors.


“We want the opportunity to have the cars in their final form before we enter the Roar,” he continued. “It not only allows us to work on our scrutineering processes with tech inspection, but also make sure that all our electronic systems are compatible with the electronics that each of the manufacturers is running, as well as the spec hybrid components that are in the car. There may be items that need to be finessed or looked at, and it’s better to do that in December versus facing that at the Roar, where we have very short turnaround time before the Rolex (race).”


Sharing Information Is Good … to a Point


During the two years that the LMDh cars have been in development, manufacturers were encouraged to communicate with the sanctioning bodies in an effort to keep the homologation process moving smoothly. There was also an unprecedented level of information sharing among the manufacturers when Porsche handled initial testing of the common hybrid system components supplied by Xtrac, Bosch and Williams that will be used by all the manufacturers.


However, that spirit of cooperation quickly fades when it comes to homologation and final approval from IMSA and the ACO.


“Homologation, that gets quite a bit more ‘personal’ because you start to get into the intellectual property of the car and the details of what’s going on,” HPD’s Crawford said. “For homologation – even the schedule – if I were to go up to Cadillac and ask, ‘Are you one week away or six weeks away from getting a signature on your document?’ I wouldn’t expect an answer.


“It’s our top priority in the company right now to get this wrapped up,” he added. “We’re all pulling our weight on it and cooperating, and between HPD and (chassis constructor) ORECA, I would say homologation is being worked on 24 hours a day. It’s feverishly moving toward the next step, and we’ll be ready for it. Definitely, by the December test, we expect to have clarity on the homologation. I’d be really disappointed if we don’t have a signed document.”

Adam Sinclair