If you're a fan of endurance racing, then you're no doubt familiar with the 24 Hours of Le Mans. This esteemed event is the oldest endurance racing event in the world, and throughout the years, this race has always been held at the Circuit de la Sarthe near the town of Le Mans in France.
Without a doubt, however, the most iconic section of the track is the Mulsanne Straight. The Straight is, as you can probably guess from the name, a long, straight stretch of road that makes up the high-speed section of the circuit. Drivers routinely reach speeds of close to 200 mph on the Straight.
In today's article, we're talking all about the history of the Mulsanne Straight, and the speed records that have been set on it.
The Mulsanne Straight, as we've mentioned, is the most well-known section of the already-famous Circuit de la Sarthe. In French, the Mulsanne Straight is referred to as the "Ligne Droite des Hunaudières" (literally the "Straight Line of Hunaudières"). When not being used for racing, the Mulsanne Straight is a public road.
The Mulsanne Straight has undergone several changes over the years, with most of them being made in the interest of safety. The biggest changes were the addition of two chicanes in 1990, which were added with the goal of reducing the speed of cars on the Straight.
Before the chicanes were added, the Mulsanne Straight was the longest straight section of any race track in the world, running for a distance of about 6 km (3.7 miles). Considering the entire length of the circuit in its current form is only about 13.6 km long, it's kind of wild for a circuit to have a single straight section that is almost half of the circuit's length.
In the earlier days of the race when the study of aerodynamics wasn't really a thing, the high speeds that the Straight allowed were certainly a safety hazard. Drivers often had no idea if their cars would actually stay on the road once they got up to top speed.
As the years went on and the cars became more sophisticated, the issue went from the cars not handling well at high speeds to the cars not being able to handle the stresses placed on them from racing at top speed for so long.
You have to remember that the race lasts for 24 hours, and for almost half of that, drivers would be barreling down the Mulsanne Straight at literally full throttle. As was, unfortunately, the case, several drivers died over the years from accidents caused by mechanical failures on the Straight.
Thus, in 1990, it was decided that two chicanes needed to be added to the Straight to break it up into sections and reduce the top speed that drivers were able to achieve on it. Before the chicanes, cars would often exceed 220 mph on the straight, but these days the cars are usually only able to reach just under 200 mph.
The other big modification made to the Mulsanne Straight was the flattening of the Mulsanne hump in 2001. The Mulsanne hump was a small rise located near the end of the Straight, and thanks to both its elevation and the aerodynamic design of some of the race cars at the time, it had a habit of launching cars that went over it into the air.
Spectators used to be able to watch the race from alongside the Mulsanne Straight, but this is no longer possible due to safety concerns.
If you're talking about the Mulsanne Straight speed record, there are actually two different records to keep in mind; the pre-chicane speed record, and the post-chicane speed record. The stories of how both of these records were achieved are pretty interesting, as it turns out.
The pre-chicane speed record was set in 1988 by Roger Dorchy driving for the Welter Racing team. The car in question was the WM-Peugeot P88, also known as the "Project 400" which used a 3.0-litre twin-turbo V6 that produced 910 horsepower.
While most constructors at Le Mans tried to build their cars for a balance of speed, reliability, fuel efficiency, and all the other things a car needs to actually be successful at Le Mans, the Welter Racing engineers had only one goal; to build a car that would demolish the speed record on the Mulsanne Straight, everything else be damned.
During that year's event, Dorchy managed to take the P88 up to an astounding 407 km/h (252 mph) on the straight. The car had to retire soon after thanks to a host of mechanical and electrical issues, but that didn't matter; the record had been set.
It's likely that this record will never be beaten, either; only two years later, the chicanes were installed, and the Mulsanne Straight as everyone had known was no more.
After the record was set, Welter Racing and Peugeot decided to advertise that the speed they had reached was 405 km/h instead of the marginally more impressive 407 km/h. The reason was that Peugeot had a new car coming out called the 405, and they decided it would be cool if the speed record coincided with the name of their new car.
The post-chicane record is obviously not quite as impressive as the pre-chicane record (366 km/h versus 407 km/h), but the story of how it was achieved is arguably a bit more interesting. For one, no one involved ever set out to achieve a post-chicane speed record; the record was set entirely by accident.
In 1990, the year the chicanes were installed, driver Mark Blundell participated in the race in his Nissan R90CK. The R90CK used a twin-turbo V8 that made somewhere between 700-800 horsepower, which should already have been enough for some pretty serious speed.
However, a mechanical fault resulted in the engine producing well over 1000 horsepower. Specifically, the turbo's wastegate malfunctioned, causing the engine to receive way more boost pressure than it normally would.
As a result, Blundell was able to hit a top speed of 366 km/h on the Mulsanne Straight. Perhaps more impressively, he absolutely smashed the record for qualifying; the second-fastest car was a full six seconds slower around the circuit than him.