For the first time this year, 24 Hours of Le Mans, there is Hypercar and Hypercar. Or more precisely LMH as Toyotathere Peugeot or Ferrari. And some LMDh as Porsche or Cadillac. What is the difference between these two technical paths? And what does it mean?

Two standards in parallel

During the 2010s fast LMP1 created by a The golden age of agingmarked by a bitter struggle between Audi, Porsche and Toyota. THE complex hybrid technologies were very expensive, and the race for development turned into a bottomless pit. Budgets are exceeded 150 million euros per year. The result: Audi, then Porsche dropped the endurance, leaving Toyota to struggle against limited privateer teams.

Recommended solution Automobile Club of the West (ACO) and International Automobile Federation (FIA) To bring the big brands back were the Le Mans Hypercar, or LMH, rules. On the menu: a lot of freedom on aesthetics cars, allowing the public to better identify manufacturers, limited levels of resistance and downforce reduce aerodynamic investment and simplified but free hybrid systems.

During this time, IMSA American Championship created your own solution. The goal: to allow manufacturers to compete on a slightly tighter budget by multiplying common parts. This will lead to a second regulation called LMDh.

Then came the convergence phase. In 2021, the organizers of the 24 Hours of Le Mans and the World Endurance Championship announced that LMDHs are eligible to compete in their events. Today in “Hypercar” category.you will find two very different types of cars: on the one hand, the Le Mans Hypercar or LMH, on the other, the LMDh.

Note: The acronym LMDh has no official explanation. The “D” probably refers to Daytonamain event of the IMSA Championship

And from the side of the chassis?

in LMHa lot of freedom is given method, parts, concepts. Undoubtedly, the most vivid example is Peugeot 9×8. The car drives from one rear spoiler and uses its bottom to create downforce. A very bold technical choice allowed by liberal legislation.

in LMDh, manufacturers are much more reserved. This is where brands who want to get involved should conclude a contract with a specialized chassis manufacturerapproved by the organizers.

Porsche chose Canada’s Multimatic, Cadillac and BMW (arriving next year) Italy’s Dallara. And Acura and Alpine, whose car was presented on Friday, chose the French company Oreca.

Free Engines…

In LMH, as in LMDh, manufacturers are free to choose their choice heat engine, its volume or the presence or absence of a turbine. Example, Cadillac chose a large and loud one Atmospheric V8 5.5 liter working volume.

And vice versa, at Peugeotwe chose a much more compact engine with a 2.6-liter twin-turbo V6 that’s less than half the power of an American. The task: to make the Lioness rear axle as light as possible.

Another common point between the two technical paths (LMH or LMDh) is The power of the car is limited to 680 horsepower. It may vary slightly depending on the performance balance set by the FIA ​​and the ACO.

… for a hybrid it depends

where is a fundamental differenceit’s on section on hybrid systems. In LMH, you can approve a 100% thermal vehicle, as in the case of Glickenhaus or Vanwall.

And for those who choose a hybrid car, device should be placed on front wheelsmaking these cars all-wheel drive for short periods each round, onwards 190 km/h (150 km/h for Peugeot).

At LMDh, brands must choose general hybrid kit. It consists of a Bosch electric motor, Williams battery located next to the pilot and a 7-speed XTrac transmission. The torque generated by the electrical system is transmitted to the rear wheels. That’s why they are on 100% movement.

you would understand this difference between LMH and LMDhit MEDIUM for the World Endurance Championship (WEC) to attract builders with different policies and aspirations. For some, it’s a matter of demonstrating technological know-how. For others, it’s an opportunity to travel everywhere on a limited budget.

And, undoubtedly, thanks to this variety plateau 2023 is also exceptional.

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