IMSA’s LMDh regulations come into focus

Now that the 88th 24 Hours of Le Mans is complete and the Toyota Gazoo Racing team has notched their third consecutive victory in this year’s late summer twice-around-the-clock classic, the Automobile Cub de l’Ouest (ACO), the Federation International de l’Automobile (FIA) and the World Endurance Championship (WEC) can now, together with the International Motor Sports Association (IMSA) turn their collective energies towards the future of sports car racing.

The Le Mans race marked the end of an era in endurance racing and crowned champions in the FIA’s WEC final standings: Toyota Gazoo Racing earned the LMP1 title, United Autosports clinched its LMP2 team trophy while drivers Albuquerque and Hanson took the drivers’ honors, Aston Martin secured the LMGTE Pro prize. Toyota Gaza’s TS050 Hybrid prototype, after trying 20 times to win Le Mans, took home the Le Mans trophy a third time, which allows the team to keep the trophy as its spoils of victory.

The Le Mans race, customarily held in June close to the Summer Solstice and, therefore, conducted during primarily sunlit conditions, traditionally includes a press conference on the Friday prior, a gathering that can portend future organizational changes and, from time to time, celebrate the past of this classic contest. With the race being held devoid of the hundreds of thousands of fans who customarily surround the French countryside circuit that includes public roads, so, too did the conference take place in virtual manner. Only through technology would participants have knowledge of its contents.

Pierre Fillon, ACO president joined Richard Mille, president of the FIA Endurance Commission, Gerard Neveu, CEO of the FIA WEC and IMSA’s president, John Doonan to discuss new regulations afforded the top class in endurance, HYPERCAR. Prior to this year’s Rolex 24 at Daytona, this group acknowledged their agreement to make rules that would complement one another’s for the premier HYPERCAR class; those regulations were intended to be unveiled at the June Le Mans race but had to be retained until this past week.

Both the WEC-specific LMH (Le Mans Hybrid) and the LMDh (Le Mans Daytona hybrid) IMSA classes will be eligible to participate at Le Mans under the name HYPERCAR. This is intended to begin with the 2022 season. The cars will all have hybrid power mills and, to date, have several manufacturers that have shown category interest to IMSA, which is keeping those nominees close to the vest. 

There are four registered and approved chassis builders for this new racecar: Dallara, Ligier, Multimatic and ORECA. While the lower body area will be common to all manufacturers, each LMH and LMDh race car will have upper body styling that allows automotive manufacturers to bring their own styling and identification cues. There is a controlled underfloor.

Highlights of the new LMDh regulations include the car’s rolling chassis estimated cost – less engine – of about $1 million and its combined 500 kw horsepower, including the spec hybrid system from Bosch, Williams Advanced Engineering and Xtrac, the sole gearbox provider. The Bosch motor integrates with the Xtrac gearbox, while Williams’ battery integrates with Bosch’s motor controller. According to IMSA, it’s a compact assembly, installed from underneath the cockpit in a compartment isolated from the driver.

It is projected the hybrid system will perform up to 22,000 kms between rebuilds, using the locked hybrid software. Regeneration is expected to deliver a maximum of 50kw continuous power at the wheels, but this is dependent on the track being used.

Minimum weight will be just over 2,270 pounds, according to IMSA, with a maximum width of two meters, computing out to about 6-1/2 feet. Maximum length is 16.7 feet for the LMDh and there’s a common wheelbase of 10.3 feet for all four chassis. The engine/car manufacturers that have conveyed interest to both the ACO and IMSA, aside from Peugeot’s entry to LMH after several years away from sports car racing, has not yet been revealed.

By Anne Proffit