10 Things You Need to Know About Audi’s R18 e-tron Quattro Le Mans Racer

We got to join Audi Sport’s prototype team, which runs a trio of R18 e-tron Quattro race cars in the FIA’s World Endurance Championship series, at a testing session at the Circuit of the Americas track in Austin, Texas.

Now that we’re done humble-bragging about kickin’ it with Audi’s racing team and enjoying 80-degree weather for a few days, we should add that we did some work while we were down there. Specifically, as the team geared up for a new WEC season and the upcoming 24 Hours of Le Mans, we spoke to Audi Sport head Dr. Wolfgang Ullrich, veteran driver Tom Kristensen, and anyone else who’d tell us anything about the inner workings of the latest R18. Predictably, a lot of the good stuff falls under the “it’s a secret” heading, but we were able to discern 10 things about the R18 you need to know.

1. The Laser Headlights Take Instructions from Satellites



Audi found that, in race settings, adaptive headlights’ promise outran their actual capability, at least when linked directly to the steering angle. That’s why the R18’s fancy new laser high-beams’ swiveling action is GPS-linked and programmed for each track. Thus, the Audi’s peepers not only illuminate corners, but they do so just before the driver actually turns the wheel, and the angle isn’t interrupted by minute steering corrections at the car’s cornering limit. The drivers like it because, on a track, they’re already thinking about the next turn even before they’ve completed the first—and now their headlights are, too.

2. The Laser Headlights Aren’t Always On

The R18’s headlights are only laser-lit in the high-beam setting, and automatically shut off at lower speeds (we heard below 55 mph) to avoid blinding everyone in pit lane. When the lasers are off, the R18’s path is illuminated by LED low-beams.

3. Even the Headlights Are Cooled

We promise, this is the last lighting-related R18 fun fact. LED headlights require plenty of cooling, and so too do laser-powered headlights. That’s why Audi not only added ducting above and below each headlight unit to cool their internals, but also spent time in the wind tunnel to ensure the venting didn’t negatively effect the car’s aerodynamics. Hence, air passes into the lower opening, and exits through a top vent; the low-pressure zone there literally sucks air through the housing.

4. The Tires Are Narrower Than Before

In compliance with 2014 World Endurance Championship rules, the R18’s tires are actually narrower than last year. One of the drivers told us that this gives the car a more agile feeling, but also reduces the sensation of stability.

5. It’s a Most Efficient Race Car

Germans are all about efficiency, but Audi is taking the hunt for better fuel economy to a new level. The team is targeting a 20-percent increase in overall vehicle efficiency this year, with 5-percent gains each subsequent year after that. Final testing has yet to wrap up, but it sounds like Audi might just accomplish its heady goal.

6. The Fuel-Injection Pressure Is, Like, Really, Really High

When Audi first switched to a diesel engine for its Le Mans racer in 2006, its fuel-injection system pressure stood at an impressive (at the time) 21,750-ish psi. Today, that figure is an astounding 34,800 psi; the mega-high pressures improve fuel vaporization in the combustion chamber. This results in a cleaner burn and boosts power while reducing emissions.

7. It’s Louder Than Before

The R18 is famously quiet for a race car, its V-6 turbo-diesel used to emit a deep, albeit muffled, roar, but this year it gets a bit louder. Audi didn’t have specific decibel levels, but told us the noticeably increased volume is attributable to the R18’s rerouted exhaust, which now exits out of the car’s rear instead of under the floor.

 
8. Audi Tried a Porsche 919–Like Exhaust-Energy Recuperation System, But Binned It

One of Audi’s highest-profile competitors going into this season is Porsche, which debuted the advanced 919 hybrid at the 2014 Geneva auto show. The Porsche’s turbocharged V-4 engine breathes through an exhaust equipped with a vane-spun electric generator, which sends power to the car’s lithium-ion battery pack, and it turns out Audi explored using similar tech.

Audi’s setup was a bit more complicated, however, and used the turbo’s vanes to capture energy via a motor/generator that, in turn, later could be used to spool the turbos quicker. (The system was separate from the flywheel-based kinetic energy recovery system (KERS) powering the R18’s front axle.) Trouble is, Audi didn’t see much of a reduction in turbo lag, so, concerned about potential reliability snafus, it shelved the idea in favor of a more-or-less carryover turbocharger with variable vane technology.

9. The Flywheel Spins Really, Really Fast

The R18 captures kinetic energy that otherwise would be lost under braking in a novel way: with a flywheel-based KERS setup. Essentially, when spun, the front axle motor/generator sends electricity to a separate electric motor fitted to a flywheel. The flywheel’s motor spins it up to a whopping 40,000 rpm, and because it lives in a vacuum, the flywheel stays spinning, storing the energy. Releasing the energy is as simple as re-engaging the flywheel motor, which, when spun, acts as a generator, sending electricity to the front axle motor.

10. The R18 Probably Is Going to Be Called the R18 for a Long Time

When asked whether future iterations of the R18 might adopt a different name, Audi Sport leader Dr. Ullrich answered with what we initially believed to be a joke: All the logical names for the R18’s successor are taken. It turns out he wasn’t kidding. Renault, for some reason, holds trademarks on a good deal of R-plus-number monikers from “R 19” through “R 35,” and even some beyond (we tired of searching the European trademark database after “35”). Audi did have a trademark on “R19,” but it seems that might have been too close for comfort for Renault, and Audi’s claim lapsed in 2011.