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[h=2]The complicated art of driving an LMP1 car[/h] Friday, 16 June 2017


Gary Watkins / Images by JEP/LAP & Porsche AG

Racing an LMP1 hybrid isn't just about driving fast. Sure, that's part of it, but as factory Porsche driver Nick Tandy explains, there's way more to it.
The art of winning in just about any category of motorsport has been likened at some point – rightly or wrongly – to a game of chess. Porsche driver Nick Tandy extends the analogy when talking about the complexities of bidding for victory at the 24 Hours of Le Mans in a factory hybrid LMP1 prototype.
"The hybridization of the cars has turned a game of chess into three-dimensional chess," says Tandy, who this year gets a belated chance to bid to repeat his 2015 Le Mans victory with Earl Bamber and Nico Hulkenberg as part of Porsche's full-season lineup in the FIA World Endurance Championship.
It's the technical sophistication of the modern breed of LMP1 cars that makes driving the Porsche 919 Hybrid different from pedaling a GTE class 911 RSR, the car in which Tandy and Bamber returned to the 24 Hours last year after both Porsche and Audi were forced to slim down their Le Mans campaigns to two cars. That and the speed at which everything happens in the cockpit.

"Everything happens much quicker in the prototype, and the faster you go, the faster things go wrong," explains the 32-year-old Briton, who's teamed with two former WEC champions in Neel Jani and Andre Lotterer in the No. 1 919 Hybrid in this year's WEC. "You have less time to react in a prototype.
"But it's the complexity of the P1s today that makes them so different, and different to just about every other class of car on the planet. There's so much you can play around with inside the car to optimize the potential and go faster, although I can't go into detail about exactly what we do – I'm not allowed to!"
The explanation is the front-axle motor generator unit (MGU) of the P1 Porsche that turns the 919 into an all-wheel-drive racecar for significant portions of each lap. That creates a massive contrast with the Porsche 911 RSR, the previous generation of which Tandy raced in the GT Le Mans class of the IMSA WeatherTech SportsCar Championship in 2014-'16, as well as Le Mans last year. The only things that can be changed on the hoof in the rear-wheel-drive GTE car are the brake bias and traction control.

"Having two driven axles gives you more scope to vary how the car is working on corner entry and exit," he explains. "The tools available inside the car to change the handling are vast, and they can all be tuned to each part of the corner courtesy of the all-wheel-drive system and the energy-recovery on the front axle. Changing something on one axle will alter how the other one works at different points through the corner. It's very complex."
The job of the team and drivers is to use the tools available to them to optimize the car for the race.

"A lot of work is done through simulation beforehand, but our job is to work through a program to get to the best possible setup in practice and qualifying," says Tandy. "There are so many pre-programmed settings on the car that it would be impossible for the driver to remember them all.
"So I'll say on the radio, for example, that we need a bit more entry stability in a certain part of the slow turns, or that we need the car to release on traction a bit more on the front axle on the exit of the faster corners. Then, my engineer will come back and say I need to select blah, blah, blah. That will happen multiple times through a practice session.
"You tend not to change much at all in the race. You might get to a position, especially over the 24 Hours at Le Mans, where the track evolves and you could be having some kind of handling issue, and that's when you start making changes again. Or if it starts raining."
The complexity of driving one of today's twin-hybrid P1s doesn't stop once setup is sorted ahead of the race. The amount of retrieved energy that can be redeployed back through the front wheels of the Porsche is limited to eight megajoules per lap of Le Mans' Circuit de la Sarthe, or 2.22kw hours of electrical energy. How it's used over the 8.47-mile track is an essential part of the P1 game in the hybrid era.

"Endurance racing is all about getting through the traffic, and these days in a P1 car traffic management is all about how you use the energy available to you," says Tandy. "You have a predetermined amount of boost out of each corner, but there might be a point where you need a little more to pass the car that you can see two or three seconds up the road before the next corner.

"Conversely you might decide that even if you use all the boost available to you, it might not be possible to make it past before the next sequence of corners. That's when you lift off and coast into the turn, knowing that you're saving energy to get that bunch of cars ahead of you on the next straightaway."

The extra dimension this adds to the art of negotiating slower cars is something Tandy enjoys.

"It makes it more interesting for the driver and gives you a chance to differentiate yourself from all the others," he explains. "If you're good at getting the most from the extra tools at your disposal, it gives you the opportunity to have a bigger advantage over a race distance than you might have over a single lap."

There are also times, says Tandy, when lifting off in a GTE car is part of the game.

"You might back off to allow a faster car, a prototype, to overtake on the straight because it benefits both parties – you won't be holding each other up in the next corner. You're saving fuel as well, so that means there's time to be gained in the pits."

There is one visceral difference between driving a modern LMP1 Hybrid and a GTE car, and that's the sheer acceleration that 500bhp of power from its direct-injection V4 turbo engine and another 400bhp from the front MGU give the latest Porsche 919 Hybrid.

"The biggest difference between the two cars hit me the moment I put my foot down the first time I drove out of the pitlane when I got to test the 919 Hybrid," recalls Tandy.

"It feels exactly the same on the inside as it looks from the outside – absolutely amazing. The acceleration overwhelms everything else the car can do because it's so different to anything else out there. Nothing compares with the linear delivery of the power and torque out of a corner. The feeling was completely alien to anything I'd experienced before."

But driving a racecar is still, well, driving a racecar, no matter how extreme it is in the technology stakes.

"At the end of the day an LMP1 is still a racecar, and you have a steering wheel and four contact patches with the track," says Tandy. "Just like in any other car, you press the go-faster pedal and the go-slower pedal, and you move the turning hoop in front of you...


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