A Le Mans prototype is designed especially for endurance racing, primarily for the 24 Hours of Le Mans but also for the World Endurance Championship, the European Le Mans Series, the Asian Le Mans Series and the IMSA WeatherTech SportsCar Championship. They are built to FIA specifications. Technologically a cut above the rest of the field, prototypes are the stars of endurance racing.
There are two prototype classes:
The Le Mans Prototype 1 class has a sub-division:
The engine manufacturer is open but the type is restricted to
Pantone red 485, with white number
Equivalence of Technology (EoT)
The endurance committee may take measures to minimise differences between hybrid and non-hybrid cars, for example with the 2017 rules concerning the back aerofoil and weight restriction for non-hybrids.
To restrict hybrid aerodynamic performance, the height of the splitter has been increased and the size of the back diffuser decreased.
Fuel allowance for hybrid cars:
Manufacturers opt for one of four energy recovery system classifications (2, 4, 6 or 8 megajoules). The systems may retrieve mechanical (brakes) or heat-related (exhaust) energy. The fuel allowance depends on the classification chosen.
Tyres for use on a wet track are not restricted in number. However, the allowance for dry weather tyres, or slicks is 28 for the practice sessions and 48 for the race.
An LM P2 is purpose-built for racing. The class is open to privateers.
Until 2017 open- or closed-cockpit cars were accepted. However, the regulations introduced on 1 January this year require closed-cockpit designs only. In theory, open-cockpit cars built before the regulations came into force would have been accepted this year, but in practice all entries for 2017 comply with new rules. The selling price of a complete LM P2 is capped at 483,000€.
Dallara, Onroak Automotive (Ligier), Oreca and Riley are the four constructors selected to supply LM P2 chassis. Gibson is sole supplier of engines for the class.
Fuel Tank Capacity
The Le Mans Grand Tourisme (LM GT) class is for two-door road-legal sports cars with at least two seats. They must have been produced in a series of at least 300 in the previous two years although other rules apply to cars authorised before the current rules introduced in 2016.
The class has two sub-categories:
The LM GTE Am class only accepts cars that are at least a year old so the 2016 rules will be taking real effect this year.
Maximum measurements for cars accepted from 2016:
Maximum measurements for cars accepted before 2016:
LM GTE Pro: Pantone green 355, with number in white.
LM GTE Am: Pantone orange 021C, with number in white.
Balance of Performance
The endurance committee reserves the right to adjust performance, based on the lap average statistics, with the fastest car as a reference.
Amendments may affect:
Fuel Tank Capacity
Tyre manufacturers may declare up to three dry weather tyre specifications, which may be different for the Pro and Am categories.
For the amateur class only, the tyre manufacturer may declare one wet-weather and one intermediate specification per model of car.
Tyres for use on a wet track are not restricted in number. However, the allowance for dry weather tyres is 32 for the practice and qualifying sessions and 60 for the race. This rule applies to both LM GTE Pro and Am.