The New Audi R18 Le Mans Car Still Beats That Wacky Diesel Drum
Audi's latest World Endurance Championship warrior looks like the Batmobile on acid, packing over 1,000 hp into an ultra-light body with Audi's most powerful hybrid system yet. The R18 name has been around for quite some time, but this year's model has been completely redesigned. It's still a nutty diesel, and that's great.
Audi's Volkswagen Group sister-marque Porsche dominated the LMP1 class of the World Endurance Championship last year. Porsche won Le Mans, and won the season championships for the class. To Audi, that's backwards. They're the marque that had won Le Mans for five years in a row before Porsche crashed the party. Fortunately, this means that Audi put a ton of development resources into this year's car.
Let's get the heffalump in the room out of the way first: yes, it's still a V6 turbodiesel. That being said, Audi's incredibly successful Le Mans prototype program is the best advertisement the Volkswagen Group has for its beleaguered TDIs. After all, the 2016 car was well in the works long before Dieselgate was a big, public snafu.
Volkswagen needs something—anything—that can demonstrate that their many TDI models aren't Satan incarnate at this point, even if that one good thing has precious little in common with their road cars. Go forth, my child, and redeem the good name of sweet diesel torque to its rightful throne in a sweet A7.
With this year's version of the R18's V6 TDI and the team's move from the 4-megajoule hybrid class to the 6-megajoule class, Audi claims that the entire package uses 10 percent less fuel. That's crucial for spending less time in the pits, and more time turning laps. The 6MJ hybrid also recovers 50 percent more energy than last year's hybrid system, so hopefully this means Audi can take the fight to Porsche and Toyota.
The R18's hybrid uses a motor generator unit (or MGU for short) on the front axle to generate power. When the driver brakes, the MGU converts the rotary motion of the front axle into power that can be used later. The power is stored and released when the driver accelerates again, sending forth a blast of electric torque to pull that front axle at ludicrous speed out of turns.
Audi claims that their new MGU is so good at recovering energy, it had to be limited in power output from 476 hp to 408 hp to meet the power limits in place for the 24 Hours of Le Mans. That's remarkable given that the R18 drivers are only on the brakes for three to five seconds at a time.
Like Toyota, Audi is moving away from its flywheel-based energy storage to big ol' batteries. Audi's new R18 features its first lithium-ion storage system for excess hybrid power.
Audi Sport Head of Electrics, Electronics and Energy Systems Thomas Laudenbach explained that the old flywheel method of storage just wouldn't cut it anymore in a company press release:
The flywheel accumulator definitely proved viable for the lower energy classes, but due to the fact that we now have to process even more energy than before, a technology change suggested itself.
Being able to store more hybrid power is a good thing, as the 4-liter V6 TDI engine was given less fuel to work with this year. They've kept with a 120-degree cylinder bank angle, a double-flow mono VTG turbocharger, and the exhaust that comes out of inside the V-angle—all of which dates back to the first generation of this engine in 2011. However, Audi says that their 2016 engine is 32.4 percent less thirsty for fuel than that 2011 engine.
Of course, it's not just the power systems that have gotten a complete recharge. According to Audi, the entire car has been redesigned to feature better packaging and lighter weight components. The mounting points for the front suspension on the all-new monocoque, for example, had to be moved to make way for the hybrid system's drive shaft. Items ranging from the car's gearbox (now with six gears instead of seven to save weight, and optimized for minimal RPM jump between gears) all the way down to individual actuators (now controlled by a high-pressure central hydraulic system) have shed weight for this year as well.
The aerodynamics and overall shape of the car have been completely changed for this year, too. Those funky pointed endplates and a new, slimmer nose are among the most noticeable changes for this year. Revised proportions help give the car a more balanced weight distribution. Ducts and vents guide air through the underfloor and out the diffuser. The openings in the front wheel arches are now 45 percent larger than last year in order to prevent lift caused by lateral airflow.
Even the lights on the car—a combination of high-powered Matrix LEDs and Audi laser lights—are optimized to allow the driver to see at night at speeds of over 210 mph.
Will the Volkswagen Group's last hope for diesel fans bring Audi another Le Mans win? We'll see this year. In the meantime, here are some more photos of the new R18 in Audi's crazy striped livery, and you can check out their launch video here for even more close-ups of the 2016-spec R18.
Photo credits: Audi