The top class of modern endurance racing — the one fighting for the overall win — is called Hypercar in the FIA World Endurance Championship (and GTP in North America's IMSA series). What makes it unusual is that it is built to two different rulebooks that race together as one class: LMH and LMDh. A Balance of Performance system nudges the two sets of cars to a similar pace so either can win outright.
LMH — Le Mans Hypercar
An LMH car is designed from the ground up by the manufacturer — the chassis, bodywork and engine are all bespoke. A hybrid system is optional: if fitted, the petrol engine drives the rear axle and the electric motor powers the front axle, so the car is effectively all-wheel-drive above a set speed (the front motor isn't allowed to deploy below roughly 190 km/h, which limits the advantage in the wet and at low speed). There is no chassis cost cap, so LMH offers the most engineering freedom at the highest cost.
Manufacturers on the LMH route include Toyota, Ferrari, Peugeot and Aston Martin — the Aston Martin Valkyrie is the outlier, racing with a naturally-aspirated V12 and no hybrid at all.
LMDh — Le Mans Daytona h
An LMDh car is built on a spec "backbone" — a chassis from one of four approved constructors (Dallara, Ligier, Multimatic or Oreca) plus a common hybrid system (motor by Bosch, battery by Williams, gearbox by Xtrac) that delivers its power to the rear axle only. The manufacturer supplies its own engine and bodywork on top. The spec parts keep the chassis cost capped at roughly €1 million, and — crucially — an LMDh car is eligible for both the WEC and IMSA, so one design can race on two continents.
Manufacturers on the LMDh route include Porsche, Cadillac, BMW, Lamborghini and Alpine, with Genesis joining as an LMDh newcomer in 2026 (on an Oreca chassis). (BMW's M Hybrid V8 runs an LMDh Dallara chassis — despite the class being named "Hypercar".)
The differences at a glance
- Chassis — LMH: bespoke, built in-house. LMDh: one of four spec chassis.
- Hybrid — LMH: optional, front axle (possible AWD). LMDh: mandatory, spec, rear axle only (always RWD).
- Cost — LMH: no chassis cap. LMDh: ~€1m chassis cap.
- Where they race — LMH: WEC / Le Mans only. LMDh: WEC and IMSA.
- Shared — both hit a common ~1,030 kg minimum weight and similar total power (~500 kW), equalised by Balance of Performance.
Both approaches now sit on the same grid, which is why a Ferrari (LMH) can fight a Porsche (LMDh) for the same overall win. For how the wider field is organised, see the classes at Le Mans.