The development of the LMH class arose following the exits of Audi and Porsche from the FIA World Endurance Championship after the 2016 and 2017 seasons, respectively, in the wake of the Volkswagen emissions scandal. Spiralling costs in the LMP1 Hybrid sub-category contributed to the need for revised regulations, as stated in the corpus. Initially, plans focused on a single, low-power hybrid system, potentially unifying top-level sports car racing with IMSA’s regulations and allowing competition in the “triple crown” – the 24 Hours of Daytona, 24 Hours of Le Mans, and 12 Hours of Sebring.
Early concepts for the new class, presented in June 2018, envisioned design concepts based on hypercars, with a targeted full-season budget in the region of 25 million euros—75% lower than existing LMP1 budgets. The initial regulations, announced at the 2018 24 Hours of Le Mans, allowed for a free engine architecture, with options for turbocharged or naturally aspirated designs. The cars would have an overall weight of 980 kg with a controlled weight distribution. A hybrid system would deliver 200 kW to the front axle, creating a four-wheel drive layout. The engine's maximum performance target was set at 520 kW.
Scuderia Cameron Glickenhaus was the first manufacturer to officially indicate its participation in the new rules in July 2018, releasing images of a planned Le Mans prototype. However, by the end of the year, Glickenhaus remained the only committed manufacturer, leading to concerns about tight timelines for development. McLaren announced in October 2018 that they would not participate in the first year of the category due to these concerns.
The regulations evolved further on 5 December 2018, mandating production-based powertrains and requiring manufacturers to produce a minimum of 25 road cars fitted with the combustion engine and energy recovery system by the end of their first season, increasing to 100 by the end of their second. This meant that non-OEM racecar constructors would not be permitted to build hypercars, effectively excluding them from participation. The maximum power output was set at 785 hp, with the electric component limited to 200 kW.
Further adjustments were made on 11 May 2020, decreasing maximum power output to 500 kW and minimum weight to 1,030 kg. In 2021, the IMSA and ACO announced a convergence of their respective sports prototype rulesets, allowing LMH cars to compete alongside LMDh cars in both the FIA World Endurance Championship and IMSA SportsCar Championship. This convergence was further extended in 2025 to include participation in the Asian Le Mans Series starting from the 2026/27 season.
LMH cars have a minimum frontal surface area of 1.6 m2. Bodywork must not reveal mechanical components unless explicitly permitted or consistent with the original car design. Movable aerodynamic elements are prohibited. Engine design is free, but limited to four-stroke petrol engines, with restrictions on modifications to production-based engines. Hybrid systems are regulated, with a maximum electrical DC power of 200 kW and specific speed limitations for deployment based on the Balance of Performance table.
This article is based solely on the corpus provided: a Wikipedia article on Le Mans Hypercar. No external sources, such as primary archives, autobiographies, period programmes, or specialist publications, were consulted.