I extend the middle digit of my left-hand; tweak a tiny titanium paddle; release the frustration of 160 horses and transform a ‘normal’ 911 racing car into something quite extraordinary. This is the Porsche 911GT3 R Hybrid, a million dollar test bed that could yet prove one of the most significant sports cars of recent years.
This is the very car that led the Nurburgring 24 hours race until the 22nd hour when, ironically, an engine valvespring threw a strop. At the Nordschleife, its combination of a 480bhp, 4.0-litre flat six and a flywheel hybrid system proved invaluable, matching the pace of the standard GT3 R’s, but bettering their fuel consumption by 25%.
The flywheel was developed by the Williams F1 team in 2008 in response to new rules allowing KERS (kinetic energy recovery systems), although it was never actually raced. With KERS banned in F1 for 2010 (it returns next year), Williams needed an outlet for its work, prompting an unlikely alliance with Porsche.
The physics are schoolboy simple. The flywheel fills the space vacated by the passenger seat and is used to power two electric motors located in the nose. They drive each of the front wheels and offer a combined output of 120kW, or 161bhp. When you brake, the electric motors reverse their role and act as generators, recharging the flywheel which stores the energy mechanically as rotation energy.
"A flywheel solution has a key advantage compared with a battery," says Hartmut Kristen, head of Porsche motorsport. "With a battery-based solution, you can't collect all the energy because to do so would overpower and destroy the batteries. But with a flywheel, that problem ceases to exist." Fully charged, the system offers 6-8 seconds of boost.
Porsche’s works driver Jörg Bergmeister has spent more time in the Hybrid than anyone else. "The system’s not just for the straights,” he says. “Because it powers the front wheels, you can use it to pull you out of corners. In the wet in particular, that's a really big advantage." It’s like having a turbo, except that it deploys its boost instantly, exactly when you want it.
A tight second-gear left-hander at the Eurospeedway Lausitz in Germany leads on to the back straight. It's adverse camber and the car bogs a little as the rear tyres struggle for purchase. A tweak of the paddle and a wallop of torque ignites the front tyres. There's a wiggle of protest through the steering wheel and then the car just picks up and flies. Six seconds of boost later and we're in fifth gear at 150mph. This system is genius.
For road cars, Porsche is more likely to persist with battery-based hybrid systems but don’t bet against this flywheel system becoming a more common on the racetrack as Porsche demonstrates its ‘Intelligent Performance’. Never before has efficiency been so much fun.