This weekend is the 83rd running of one of the most prestigious events in all of motorsports->ke447 – the 24 Hours of Le Mans.->ke1591 It’s often called the ultimate test of man and machine, and it promises to bring together the biggest names in the auto industry and the fastest drivers in racing to duke it out for ultimate glory.

The 24 HOLM is filled with history, but at the same time represents the bleeding edge of four-wheeled technology. It’s one of the most demanding events in the world, with a plethora of different classes on track at once, offering plenty of opportunities for disaster. Conditions change constantly, with the usual gamut of variable weather and track conditions compounded by the setting and rising sun. A win here means far more than a whole season in most other series.

This year, the event will see four factory-backed entries into the top echelon LMP1 class, providing a good deal of drama for race fans. Who will come out on top? You can download the full car-spotter guide here.

Continue reading for the low-down on this iconic motoring event.

The Track

In many ways, the Circuit de la Sarthe is a unique track. First, it employs sections of local roads that are open to the public throughout most of the year, which can lead to less than ideal grip. In its current configuration, a single lap distance is 8.47 miles, making it one of the longest racing circuits in the world. Despite several modifications, the track also employs extremely long straights, with drivers spending 85 percent of each lap at full throttle.

This makes for absurdly high speeds (Roger Dorchy achieved a record 251.1 mph in a Peugeot->ke68 in 1988), which means a well-balanced aerodynamics package is particularly important. The high speeds also put tremendous strain on mechanical components, with engines maxed down the straights, and the brakes, suspension, and tires maxed when slowing down at the end of them.

The result is an ideal battleground for endurance racing, lending credence to the phrase “to finish first, you must first finish.”

LMP1

Considered the premiere class at Le Mans, these spaceships-for-the-tarmac feature the highest speeds and most advanced technical sophistication on track.

2015 Audi R18 e-tron quattro

Since the year 2000, Audi->ke14 has enjoyed relatively undisputed domination at Le Mans. But with three additional factory-backed teams vying for supremacy in 2015, it looks like that streak could come to an end.

Still, you have to respect Audi’s record: the automaker has claimed victory at 13 of the last 15 events. What’s more, it’s also won the first two opening rounds of this year’s World Endurance Championship at Silverstone->ke1009 and Spa.

Behind the wheel will be the right talent, with three-time Le Mans winners Andre Lotterer, Marcel Fassler and Benoit Treluyer gunning for a fourth win in five years.

Olivier Jarvis, a new driver for Audi, had this to say to the U.K.-publication AutoExpress: “Porsche definitely has more hybrid boost out of the corners, but on a very long straight, like at Le Mans, we’ll hopefully catch up once they’ve used their boost. The longer the straight and the higher the speed, the closer we get to them. Where we lose out is in tighter corners that are followed by short straights.”

While visually similar to last year’s car, Audi went to great lengths to improve the new, fifth-generation R18. The aero is tweaked for less drag, while the drivetrain has been bumped up from the 2-mega-joule class to the 4-mega-joule class. Both output and efficiency of the engine have increased, with the car’s 4.0-liter V-6 diesel unit delivering 550 horsepower while burning 2.5 percent less fuel per lap.

Audi remains the safest bet to win the race outright, gaining speed and cutting consumption while maintaining bulletproof reliability. But it’ll need a world-class performance to stay in front in the midst of its challengers.

Read our full review of the 2015 Audi R18 here.

Toyota Gazoo Racing TS040

Last year, Toyota->ke88 was considered far and away the fastest car in the WEC, besting Audi in both the manufacturer and driver’s titles with five wins out of eight races. However, Toyota still came up short at Le Mans, losing out to Audi in the final hours of the race due to technical issues.

For 2015, Toyota’s revised TS040 Hybrid has been thrown back on the development cycle, unable to keep pace with Audi and Porsche->ke1 at Silverstone and Spa. But it isn’t for lack of trying – the new car received updated aerodynamics, suspension changes, and alterations to its hybrid->ke147 system. The car makes 200 horsepower more than the challengers from Audi, but has proven to be a handful on the track.

Nowhere was this more apparent than at Spa this year, where driver Kazuki Nakajima suffered a fractured vertebra in an off-track excursion during practice. However, Nakajima has reportedly healed fully, and just in time for Le Mans. Mike Conway, known for competition in IndyCar->ke1559 road and street tracks, will join Nakajima to make his second appearance at Le Mans, while other notable drivers include Sebastien Buemi, Anthony Davidson, Stephane Sarrazin, and Alex Wurz.

Toyota remains Japan’s best hope for clinching victory at Le Mans, with the island nation’s last (and first) win at the prestigious race coming in 1991 with the 1991 Mazda 787B.

Read our full review of the 2014 Toyota TS040 here.

Porsche 919 Hybrid

With 16 wins to its name, Porsche is defending its position as the all-time record-holder for most successful manufacturer at Le Mans. However, the last time Porsche tasted victory was in 1998, and Audi is dangerously close to snatching the title, thus prompting Porsche’s return to the sport last year.

However, things are looking good for the marque. Porsche managed to grab a 1-2-3 in the first qualifying session this year, and also took pole in each of the opening rounds of the WEC. What’s more, the marque got fastest lap in pre-race testing with a 3:21.061, about a second quicker than the race lap record.

Still, it’s going to take more than sheer, outright speed to win the 24-hour event. To help bolster it’s efforts, the new 919 Hybrid->ke4873 moves to the highest energy class of 8-mega-joules, with internal combustion provided by a turbocharged 2.0-liter V-4 driving the rear wheels, while electric power comes through the front.

The driver lineup sees two Formula 1->ke190 names make an appearance: Mark Webber and Nico Hulkenberg. Other standouts include Neel Jani, Romain Dumas, Marc Lieb, and Brendon Hartley.

While undeniably fast, Porsche’s recent efforts in this highest form of endurance racing have proven to be unreliable and quite hard on the tires. Still, Porsche is the best bet when it comes to challenging the dominant vehicles put forth by Audi.

Read our full review of the 2015 Porsche 919 Hybrid here.

Nissan GT-R LM NISMO

The last time Nissan->ke62 went racing at Le Mans was 16 years ago, and now the marque returns with a radical new car. Masterminded by mad scientist Ben Bowlby, Nissan’s prototype racer snubs convention by employing a front-engine, FWD layout. While particularly tough on the front rubber, Nissan hopes this setup will allow for improved aerodynamics and efficiency.

Here’s the logic: with all the mechanical components in the nose, the front section of the car is extended, offering higher levels of downforce. Furthermore, the middle sections of the car will be relatively empty, allowing for channels and ducts that direct the air flowing around the racer for reduced drag. And like your Grandma’s commuter eco-box, FWD does away with the parasitic loss normally associated with sending power to the back.

It’s a gamble, no doubt about it, with development essentially starting from scratch about a year ago, making Nissan unquestionably the underdog for 2015.

Drivers include GT Academy winners Jann Mardenborough, Lucas Ordonez and Mark Schulzitski, while ex-Formula 1 driver Max Chilton and sports-car expert Olivier Pla also join the roster.

So far, things aren’t looking great for Nissan. Originally slated for a full season of the WEC, the team was forced to pull out of the first two rounds of 2015, presumably due to technical issues. However, Le Mans is Nissan’s primary target, and the car has shown incredible velocity in the straights. Maybe, just maybe, the 24 hours will be more than just another development session for one of the most radical prototypes in history.

Read our full review of the 2015 Nissan GT-R LM Nismo here.

LMP2

As the second prototype category, this classification still lies outside the requirements of a production minimum, but is designed for teams independent of manufacturer support, with strict caps on costs and a mix of both amateur and pro drivers. This year sees 19 starters in LMP2, a huge increase over last year’s relatively sparse field of entries. Here are a few standouts:

G-Drive Racing

Last year, G-Drive almost took victory in the LMP2 category, leading the race right up to the end, when mechanical issues knocked the team back to fourth. This year, G-Drive is still looking like it will be out front, as it leads in points with a very strong start to the 2015 WEC season, not to mention a full year of development already on the books.

The team will field two entries, the No.26 and No.28 cars, both of which are Ligier JS P2 Nissans equipped with tires from Dunlop. Driving the No.26 car will be last year’s drivers, Roman Rusinov and Julien Canal, while Sam Bird, a former GP2 race winner, will replace Olivier Pla. The No.28 car, which currently leads the championship, sees a driver lineup hailing from Latin America, with Luis Felipe ‘Pipo’ Derani, Ricardo Gonzalez, and Gustavo Yacaman behind the wheel. Oak Racing will provide technical support and pit crews.

KC Motorgroup

Hailing from Hong Kong, KCMG started with touring car, sports car, and open-wheel racing in a variety of Chinese and Japanese series before expanding into the 24 HOLM in 2013. In 2014, the team entered the full WEC season, winning three races in the process. This year, KCMG sits at third in the championship, just a single point behind the No.26 G-Drive car.

Fielding the No.47 Oreca 05 Nissan (also running Dunlop tires), KCMG employs Matt Howson and Richard Bradley for driver duties, both of whom raced with the team in the 2014 WEC season. Joining them is Nicolas Lapierre, who replaces the Porsche LMP1-bound Nick Tandy.

LM GTE Pro

Here, we find vehicles that start to resemble those you could see parked in your driveway. Names like Ferrari,->ke252 Aston Martin,->ke13 and Corvette->ke1280 abound, as late-model sports cars fitted with enormous aero enhancements and a slew of go-faster modifications battle amongst the pace-leading prototypes.

AF Corse Ferrari

Founded in 1995 by racing driver Amato Ferrari and backed by the Italian marque of the same name, this team competes in a variety of racing series worldwide, boasting over 100 GT cars under its banner. Despite a huge, widespread effort, AFC consistently finishes among the top ranks and has a good number of championship titles to its name, including several in the WEC.

AFC will put two 458 Italias->ke3479 in the running at Le Mans, including the #51 car under the guidance of Gianmaria Bruni, Giancarlo Fisichella, and Toni Vilander. The No.51 looks to be a favorite for the category win, with a victory in the opening round at Silverstone and a near victory at Spa (a pit penalty forced them from the podium). Complementing the No.51 will be the No.71 458 Italia as driven by Olivier Beretta, James Calado, and David Rigon.

Aston Martin Racing

AM has a long history at Le Mans, and that story continues into 2015 with a trio of V-8 Vantages.->ke4410 This triple threat should offer the Brits some pretty good odds in France, especially when considering their second-place standing in the world championship points, a result mostly thanks to a first-place finish at Spa.

Look for the No.95 car driven by Christoffer Nygaard, Marco Sorensen, and Nicki Thiim, the No.97 car driven by Rob Bell, Stefan Mucke, and Darren Turner, and the No.99 car driven by the all-rookie lineup of Alex MacDowall, Fernando Rees, and Richie Stanaway.

Corvette Racing

Representing American sports cars,->ke506 GM’s factory effort at Le Mans brings two 2015 Chevrolet Corvette C7.Rs to France as it looks to add another victory to its record. Unfortunately, the last time the team took home a win in GTE was in 2011, but doesn’t mean you should count it out. While thirsty, the big V-8s should have the power for the long straights, while the driver lineup is top notch.

Driving the No.63 car is Ryan Briscoe, Antonio Garcia, and Jan Magnussen. Both Garcia and Magnussen have extensive experience on the podium at Le Mans, while Briscoe will be looking to make a triple crown after victory at Daytona and Sebring. Meanwhile, Olvier Gavin, Tommy Milner, and Jordan Taylor, each also a hardened Le Mans veteran, will man the No.64 car.

LM GTE Am

Like the name suggests, this category also brings production vehicles to bear, but encourages the participation of “gentleman drivers” with backing from private enterprise, with at least two non-pros on the roster required for entry. Factory support is present, but more limited than in GTE Pro.

Riley Motorsports-TI Auto

When Dodge/SRT pulled the plug on its GTE program, it left a well-developed 2014 Dodge Viper GTS-R in the hands of Bill Riley. Taking full advantage of the well-sorted V-10 rocket, Riley enlisted the support of TI Automotive and decided to bring the snake to the fight in France for 2015.

Equipped with Michelin tires, the No.53 Viper->ke1404 will be driven by Jeroen Bleekmolen, Ben Keating, and Marc Miller. This will be Bleekmolen’s 10th start at Le Mans, as he hopes to add to a resume that already includes a win in the LMP2 category.

Dempsey Racing-Proton

Sure to be a fan favorite, celebrity-actor-turned-racer Patrick Dempsey once again returns to Le Mans in the Michelin-shod No.77 2013 Porsche 911 RSR. Dempsey knows the track well, and has experience leading out front, showing good pace in the past. The team currently sits at sixth in points, scoring a sixth place finish at Silverstone and a fifth place finish at Spa. Joining Dempsey is Pat Long, who brings experience as a factory Porsche driver with 11 Le Mans starts, while Marco Seefried, a solid silver-class driver, rounds out the roster.

The Schedule

Note: all times are local.

Thursday, June 11th

4PM – 5PM: Qualifying practice session (Le Mans Legends)

5:30PM – 6:30PM: Qualifying practice session (Support Series)

7PM – 9PM: Qualifying practice session (24 HOLM)

10PM – 12AM: Qualifying practice session (24 HOLM)

Friday, June 12th

9AM – 4:30PM: Classic British Welcome

5:30PM – 7:30PM: Driver’s Parade

Saturday, June 13th

9AM – 9:45AM: Warm up (24 HOLM)

10:05AM – 10:50AM: Race (Le Mans Legends)

11:15AM – 12:00PM: Race (Support Series)

3:00PM: 24 Hours of Le Mans race begins

Sunday, June 14th

3:00PM: 24 Hours of Le Mans race finish

Origins and History

The first 24 HOLM was run in 1923, and was originally held on public roads around the French town from which the race derives its name.

After a decade-long hiatus between 1939 and 1949, racing resumed with major factory backing, including entries from Ferrari, Aston Martin, Mercedes-Benz,->ke187 and Jaguar.->ke39

Throughout the ‘50s and ‘60s, vehicle speeds increased substantially, prompting additional safety measures for both the drivers and spectators. One example was the way in which the race started.

Traditionally, a “Le Mans start” saw drivers and cars lined up on opposing sides of the front straight. When the green dropped, the drivers would sprint across the track, enter their cars, and get underway.

While exciting, many drivers would ignore safety devices. In 1969, Jacky Ickx protested the tradition by walking to his car while his competitors ran. Privateer John Woolfe died in an accident on the first lap, while Ickx ended up winning. The tradition was changed the following year, and now, the 24 HOLM begins with a rolling start.

The ‘70s saw rapid development of aerodynamics and efficiency technologies, while additional manufacturers, like Japanese marques Toyota, Nissan, and Mazda->ke53 entered the fray in the late ‘80s.

In the ‘90s, a variety of famous exotic supercars were built to compete in the Grand Touring category, such as the 1995 McLaren F1 GTR. The year 2000 saw the beginning of a dynasty for Audi in the prototypes class, which introduced new diesel and hybrid technology to the sport over the course of the following 15 years.