24 Hours of Le Mans

The 24 Hours of Le Mans (24 Heures du Mans) is the world's oldest sports car race inendurance racing, held annually since 1923 near the town of Le Mans, Sarthe, France. Commonly known as the Grand Prix of Endurance, it is organised by the Automobile Club de l'Ouest (ACO) and runs on a circuit containing closed public roads that are meant not only to test a car and driver's ability to be quick, but also to last over a 24 hour period.

At a time when Grand Prix racing was occurring throughout Europe, Le Mans was envisioned as a different test from motorsports. Instead of focusing on the ability of a car company to build the fastest machines of the time, the 24 Hours of Le Mans would instead concentrate on the ability of manufacturers to build sporty yet reliable cars. This would drive innovation in not only reliable but also fuel-efficient vehicles, since the nature of endurance racing requires as little time to be spent in the pits as possible.

At the same time, due to the design of Le Mans, a drive would be created for better aerodynamics and stability of cars at high speeds. While this was shared with Grand Prix racing, few tracks in Europe featured straights the length of the Mulsanne. The fact that the road is public and therefore not maintained to the same quality as some permanent racing circuits also puts more of a strain on parts, causing more emphasis on reliability.

Beginning in the late 1970s, the demand for fuel economy from around the world led the race to adopt a fuel economy formula known as Group C in which competitors were given a set amount of fuel, from which they had to design an engine. Although Group C was abandoned when teams were able to master the fuel formulas, fuel economy would still be important to some teams as alternative fuel sources would appear in the early 21st century, attempting to overcome time spent during pit stops.

These technological innovations have had a trickle-down effect, with technology used at Le Mans finding its way into production cars several years later. This has also led to faster and more exotic supercars due to manufacturers wishing to develop faster road cars for the purposes of developing them into even faster GT cars.