Unlocking the speed secrets of Volkswagen's first electric race car

For a motorsports engineer like Cedric Delnatte, the ask was a bit of a dream: Design a new electric vehicle to take on one of the world’s great racing challenges, from scratch, with no rules beyond those of physics and driver safety.

The result was the I.D. R Pikes Peak, the car that broke the overall record for the Pikes Peak hill climb in June 2018 – breaking a record that had previously only been set by liquid-fueled vehicles. The trip up the 12.42-mile route took just 7 minutes, 57.148 seconds, but before that was months of work by Delnatte and team to unlock the potential of Volkswagen’s first electric race car. At the Los Angeles auto show, Delnatte provided an insider’s tour into what made the I.D. R so fast, and a bit of a preview of what might come next.

 

From the start, Delnatte said the team quickly recognized that they would have to find a precise balance between power and weight. At 670 hp, the I.D. R has a mighty amount of grunt, but not as much as, say, a typical stock-bodied racecar. But with just under 2,425 lbs. to move, the I.D. R can accelerate more quickly than most top-level, open cockpit race cars.

Delnatte said computer simulations quickly found that limiting weight was vitally important for mastering the Pikes Peak route and its 156 corners — even if it meant sacrificing some power.

“Pikes Peak is very specific because it’s made out of corners, so having a lot of power doesn’t really help you – it helps you only on straight lines,” he says.  “You don’t need this power to be fast on the corners.”

The I.D. R Pikes Peak at the Los Angeles auto show. The racing number 94 comes from the ninth and fourth letters of the alphabet – I and D.

The other challenge was the battery pack. At 45 kilowatt-hours, the battery pack on the I.D. R can hold about 26 percent more energy than a 2018 Volkswagen e-Golf – again, a substantial but not overwhelming amount. Delnatte said the I.D. R was designed to make the most of that energy by relying on recuperation – essentially, using its twin electric motors as generators when driver Romain Dumas needed to slow down to recapture energy back to the batteries. Some 20 percent of the energy the I.D. R used to climb Pikes Peak came from brake regeneration.

Making the most of all these parts relied on extensive aerodynamic testing and chassis design. The I.D. R looks like no other car because it’s designed to slip through the air as effortlessly as possible. Every part of the car was optimized either for airflow or downforce, from the smooth floor to the massive rear wing. Since Pikes Peak racers end up at 14,000 feet, the higher altitude makes it harder to maintain downforce. The oversize wing and other parts create so much downward pressure at speed that it’s like having another I.D. R sitting on top of itself.

“If you could rotate the car,” says Delnatte, “the car would fly.”

Adapting to an electric racecar also posed some challenges for driver Romain Dumas. The low slung, centered cockpit provides great aerodynamics and limited visibility. Dumas’ seat is slightly off-center, as the battery pack has been split in two, with one half next to him and the other behind him for better front/rear weight balance. The other challenge: Just how quiet the I.D. R runs.

“It’s much less loud than a conventional engine car, which was affecting Romain quite a lot,” says Delnatte. “A driver in general is adjusting his driving style based on the noise that he’s hearing, and in this type of car you don’t hear that much.”

Now that Pikes Peak has been conquered, the I.D. R team has some other plans for the car. Next month, Volkswagen Motorsports will announce the I.D. R’s next challenge. Delnatte couldn’t discuss specifics, but he said just as Pikes Peak took months of work to master, the next target will need its own set of innovations.

“If you want to go back to a track basically at sea level, you would change the aero because you don’t need such a big rear wing,” he said. “If you go to a longer track, you would need maybe different batteries, or if you go to a track where you have more straight lines, you would need more power and less drag. So it’s really depending on the target you fix.”