In most motor sports, the engineer's cruelest enemy is not the rules of physics or the driver's inability to squeeze every crumb of power from his vehicle. Are the rules. Rules established by the governing governing bodies, which impose weight limits, dimensions, power output, tire options, aerodynamics, braking and anything else they may think to control. In general, the goal is to keep drivers safe or to make racing more fun with the same machines, but that does not mean engineers like it.
So, when Porsche gave its people the opportunity to break free and show what their machines can do, they overdelivered. They started with the 919 Hybrid, the car that Porsche used to win the 24 Hours of Le Mans in the last three years. Then they did everything that could make the car go faster, the things that would break the rules for the rest of the time. The result is called 919 Evo.
And then they took it to the Francorchamps Spa in Belgium, the legendary Formula 1 track that is home to what may be the toughest corner of motorsport. The Evo passed the course in 1: 41.77 minutes, 12 seconds faster than the 919 of the legal race. In a sport measured in milliseconds, that's a great improvement. He even surpassed the record of all time, established by the Formula 1 champion Lewis Hamilton, by 0.783 seconds.
"The 919 Evo is brutally impressive," says Neel Jani, the driver who bathed Spa. "It's definitely the fastest car I've driven, the grip level is totally new to me, I could not imagine this amount in advance"
It turns out, when you get to ignore the rules that govern the World Endurance Championship (which includes Le Mans), there's a lot you can do to go faster. Porsche engineers reduce the weight of the carbon fiber and the aluminum car by 86 pounds, to 1872 pounds, by throwing away useless motifs such as windshield wipers, lights, air conditioning, electronic race controls and the pneumatic jack. They also adjusted the exterior aerodynamics, generating 53 percent more downforce, the most important thing that keeps the car stuck to the pavement when it is setting jumbo takeoff speeds. Improved suspension and tires to deal with additional loads.
The Evo carries the same two-liter V4 engine and turbocharger as the winning Le Mans car, minus the fuel flow meter that limits the amount of gasoline spent. Combined with a software adjustment, that increased its power from 500 horsepower to 720 horsepower. The car uses two energy recovery systems, which generate electricity from braking and exhaust. It is stored in a liquid-cooled lithium-ion battery, and then used to drive an electric motor on the front axle while the engine drives the rear, for maximum acceleration with all drive wheels. Without imposed limits, that engine now adds another 440 horsepower (as much as the total power of a BMW M3), up to 10 percent.
This record lap is part of a farewell tour for the winning Le Mans car. Porsche is retiring from the World Endurance Championship to be able to concentrate on fully electric Formula E races. The next stop for the 919 Evo is what Porsche calls a "demonstration lap" at the legendary Nurburgring in Germany. Porsche previously established a career car record there in 1983 with its 956, which still stands. Then he's at Goodwood Festival of Speed, and at the Porsche Festival at Brands Hatch, in the UK, before arriving in California Seca in California.
Like many retirees, the 919 is finally ready to ignore the rules and have a little fun, on their terms.