How the tech from the crazy cars of Le Mans will make it to your garage

Influencing everything from windshield wipers to laser headlights, Le Mans is more than a grueling 24-hour race; it’s the ultimate gauntlet for automotive tech.

Originally conceived 91 years ago to prove the reliability of the fledgling automobile, the 24 Hours of Le Mans race not only achieved that goal, it has left an indelible mark on automotive technology – both on the track, and on the road.

Headlights, windshield wipers, disc brakes, diesel, and hybrids – believe it or not – are all technologies that owe their current state of existence to the 24 Hours of Le Mans. And thanks to new energy regulations for 2014 that sent every manufacturer back to the drawing board to focus on fuel efficiency, its influence will only grow in the years ahead.

So how will the competitors in this year’s race change the road cars of tomorrow? We looked under the hoods at the advanced machines competing in the cutthroat LMP1 class to find the tech that will soon be in your garage.

For Audi, the more pressure the better

Audi’s Le Mans Joest team has won the 24-hour race 12 times – more than any other team in history. Not surprisingly, many of the technologies that Audi developed for Le Mans have made their way into its production cars.

“Things that have proven to be successful here at Le Mans have a stamp so [Audi management] don’t have to argue any more ‘is this good or not?’ It’s proven that it’s good,” explains Ulrich Baretzky, the head of engine development for Audi’s Le Mans Protoype (LMP) cars.

Once TFSI proved a success, measured by Audi’s 2001 Le Mans win, the fuel system was introduced to every Audi road car one by one. By 2007, every single gasoline engine in the Volkswagen Group used TFSI.

When Audi made the controversial switch away from gasoline engines to diesel in 2006, race-team engineers instead turned their attention to Turbocharged Direct Injection (TDI) diesel engines. Keen to make more power from less fuel, Baretzky and his team pushed the limits of direct injection systems. While normal diesel engines commonly operated around 600 bar of injection pressure – an astounding 8,700 pounds per square inch – Audi doubled that to 1,200 bar.

After its success with standalone TDI, Audi turned its sights to diesel hybrids, which it calls e-tron. Though e-tron technology is entering Audi showrooms this year, in the form of the A3 e-tron, the hybrid tech Audi uses in its R18 Le Mans car is significantly different than that in the road car. But we’ll get to that in a bit.

Historically it’s taken years for technology developed for Le Mans to make its way into consumer cars. In 2014, though, Audi accelerated the trickledown process.

Audi’s No. 2 R18 e-tron quattro won the 24 Hours of Le Mans 2014, but its effects can already be felt in the production-car world. The laser headlights, which were essential for a Le Mans victory, have already debuted in the 2015 R8 LMX.

Aside from laser headlights, what current Audi Le Mans tech could hit showrooms soon? Certainly the up-rated diesel injection pressures could. If you’re hoping Audi’s move from a 3.7-liter V6 to a 4.0-liter for 2014 is an indication that the brand will begin upsizing its engines, think again.

Increased displacement is only more efficient on the track. While road drivers use full throttle around one percent of the time, racing drivers use full throttle around 70 percent of the time.

Audi used 22 percent less fuel at 2014 Le Mans than during its 2013 triumph. So how did a bigger engine prove more efficient? Essentially, a driver running full throttle on a smaller displacement engine uses more energy than one using partial throttle on a larger engine.

“If you take a 5.0-liter V8, you could create, say, with no regard to consumption, 1,300 horsepower,” Baretzky told Digital Trends. “And if you take the same engine and go down to 500 [horsepower], then you are … driving in a partial load area.”

Porsche charges back in and charges up

This year marked Porsche’s return to the top class at Le Mans for the first time since 2006 – a class in which it stands as the winningest automaker of all time (Audi Joest is the most-winning team). The new hybridization regulations drew the automaker back in.

After all, Porsche is no stranger to hybrids. It has the Cayenne Hybrid, Panamera Hybrid, Plug-in Panamera S E-Hybrid, and the 911 GT3 R Hybrid racecar. The latter uses a Kinetic Energy Recovery System (KERS) – essentially a giant flywheel that stores energy like a spring when a car brakes, then unleashes it back into the drivetrain later.

But this year Porsche opted for a lithium-ion battery-based hybrid system over the KERS system it had already developed. Why? KERS wasn’t feasible for consumer applications.

In the 911 GT3-R Hybrid, the KERS flywheel took up the entire passenger seat. Even with earplugs, the whine of the flywheel was downright deafening. Plus, it only provided six-to-eight-second bursts of energy. This sort of boost was useful on the track, but little elsewhere.

Porsche realized the average commuter would benefit from a slow energy release system, and accordingly chose batteries for Le Mans. If it was going to invest millions into the Le Mans P1 car, it wanted the lessons learned to be relevant to road cars, rather than simply race cars.

Battery technology is still too heavy to be ideal for a 911. As Engelman pointed out, “You can’t very well add 500 or 600 pounds of battery to the 911.” Still, though, Porsche sees it as the best solution to the coming fuel-economy standards, while remaining the benchmark sports carmaker.

In terms of engine technology, while Audi was opting for a larger V6 diesel, Porsche went with a gasoline V4 with just half the displacement: 2.0 liters. To capture as much energy as possible, Porsche installed a turbo-like contraption into the 919s’ exhaust system, which was spun by passing exhaust gasses. The spinning turbo unit then generated electricity, which was routed to the onboard batteries.

Audi, always a consummate competitor, was unimpressed by the Porsche exhaust energy regen system. Speaking of the Porsche exhaust system, Audi’s Ulrich Baretzky said: “I prefer to make a highly efficient internal combustion process instead of recovering energy from exhaust … As an Audi driver, I prefer to have efficiency when I start the engine.”

Porsche, unlike Audi, might not have a recent history of LMP1 car technology making its way into road vehicles, that doesn’t mean what it learned from this year’s race won’t soon affect consumer cars.

“I absolutely see 919 technology affecting road car technology in the future. Hybridization is in everybody’s future, and it’s certainly in Porsche’s future,” Engelman admitted. “I’m not going tell you the next 911 is coming along with nothing but extension cords, but … hybridization is going to be further and further spread through the Porsche line.”

For Nissan, street tech proves itself on the track

Nissan entered the 2014 Le Mans not with a LMP1 car, but with a special vehicle: the Zero Emission On Demand (ZEOD). The ZEOD (pronounced zee-odd), though Nissan considers it an EV, is technically a hybrid with an onboard 1.5-liter gasoline engine to generate electricity on-demand.

The ZEOD entered into the Garage 56 non-competitive category, which demonstrates new technology.

Though the ZEOD wasn’t intended to compete, Nissan hoped the car could complete the entire 24-hours. Unfortunately, the ZEOD’s transmission failed only 23 minutes into the race. Still, Nissan considers it a success.

Unlike Porsche and Audi, which have pushed Le Mans tech down into their road cars for years, Nissan went the opposite route with its ZEOD. To create the DeltaWing racer, Nissan pulled from its extensive all-electric LEAF research and development.

“We used a lot of existing knowledge and data that went into developing [the LEAF] … into developing the ZEOD,” said Darren Cox, the global head of brand for marketing and sales in Nissan’s NISMO performance division. “Then all that data will go backwards to road cars.”

That said, the lessons learned at Le Mans with the ZEOD will find their way into future Nissan road cars.

“[With ZEOD technology] you’d have the opportunity to go down to the store to pick up milk and bread, you could switch to electric. Now, if you had to go on a longer journey, you could then switch to petrol mode. There are currently concepts being created that incorporate those ZEOD options into road cars in the future.”

Again in contrast, Audi’s moneymen don’t need an argument for a technology once it succeeds at Le Mans. At Nissan, the tech flows freely from road car to racecar.

“With the P1 regulations, it mandates a hybrid powertrain. So there will be lessons learned through that project that we will pass on back to Nissan’s road cars of the future.”

While Nissan’s 2014 entry will affect standard production vehicles, Nissan’s 2015 LMP1 car will likely change the face of its most extreme sports car: the GT-R.

“The GT-R is the pinnacle of performance from Nissan’s perspective … and some of the DNA in the road car will be transferred across into the P1 car. As to what exactly what that will mean for the next model of the GT-R, that’s still to be determined.”

This, clearly, is an intentionally vague statement. But if we read between the lines and take Audi and Porsche as example, Nissan is taking its entry in to Le Mans P1 as a way to not only bolster the brand but also send GT-R development down a fast track – literally and figuratively.

Racing forward

The 24 Hours of Le Mans 2014 proved both harrowing and technologically significant. Next year will likely prove more exhilarating and more technologically consequential.

Rather than a three-way race between Audi, Porsche, and Toyota for the crown, 2015 will be a five- or six-way competition. Not only will Nissan enter its GT-R LMP1 car, Lotus, too, will be entering the top class of Le Mans for 2015.

Increased rivalry means more crashes, more close racing, and also accelerated performance tech development.

In the meantime, Toyota, Porsche, and Audi all meet for another endurance race this September at the Circuit of the Americas in Austin, Texas. We’ll be on the ground at the race, so be sure to watch for our continued coverage of these incredible cars.