‘EV Launches’ Under Consideration for GTP Class

Photo: Jonathan Grace

IMSA is working to finalize elements of hybrid usage in the WeatherTech SportsCar Championship GTP class, including the potential of full-electric driving on pit lane and/or mandatory ‘EV launches’ out of the pit box.

The sanctioning body, which released the initial version of its 2023 sporting regulations earlier this month, has yet to confirm several items related to the new GTP category that will see LMDh machinery compete in beginning with January’s Rolex 24 at Daytona.

Figures for the GTP stint length maximum and replenishment, as well as details on electric driving have not been finalized according to IMSA technical director Matt Kurdock.

Kurdock told Sportscar365 that mandating so-called EV launches where GTP cars exit the pit box on full electric power, has been under consideration.

LMDh manufacturers have largely been utilizing this practice in testing so far, although it’s unclear if IMSA would mandate the use of full EV power for the entire length of pit lane or just exiting the pit box.

“For sure the actual sporting regulations are associated with that aspect [of electric driving],” Kurdock explained. “If you’ve checked what we’ve published for 2023 you may note some TBDs in some areas.

“Those are details, as we’re working through the testing with the cars, we hope to be able to finalize in the coming weeks.

“Certainly the cars have the capability of EV launches.

“Whether that’s an aspect of the car that we want to get into regulating or provide manufacturers and teams the option of electing to launch on the engine instead of EV, that’s a topic that IMSA should finalize in the next update of the regulations.

“In terms of deployment on the race track, there’s been some progression on some of the control software related to that.”

Kurdock said that it’s IMSA’s objective to provide teams and manufacturers with the flexibility to use the spec LMDh hybrid system “within a certain range” of limits on deployment and regeneration.

“At certain tracks that range of continuous usage will be limited to 50 kilowatts as measured at the rear wheels,” he said. “At some tracks that may be limited to 30 kw.

“As far as the regeneration, that’s been consistent. It’s 173 kw of peak regeneration power.

“We have to have the ability of launching the car on all electric, which means we need to generate a lot more than 50 kw. That’s where the full power of the hybrid system is enabled when you get into a scenario like pit lane.”

As defined in the LMDh technical regulations, IMSA and the ACO have introduced an ‘Equity Model’ that determines the instantaneously available energy and power, cooling system performance, power request and the battery’s state of charge.

“There are aspects of the hybrid system that are self-regulating,” Kurdock explained. “There’s control software that runs on the hybrid system.

“There’s other aspects of it that remain free and open for the manufacturers to play within a certain range of parameters.

“These are the aspects that are detailed in the technical regulations. Our goal is to have a hybrid system that achieves the very stringent durability targets to run in an endurance racing environment.

“In order to achieve those endurance targets and parity of hybrid system performance from car-to-car over the life of that system, in working with the ACO and our hybrid partners, we’ve had to put in place specialized software that enables that.”

John Dagys

John Dagys is the founder and Editor-in-Chief of Sportscar365. Dagys spent eight years as a motorsports correspondent for FOXSports.com and SPEED Channel and has contributed to numerous other motorsports publications worldwide. Contact John