This may be one of the most significant racecars in recent times......but isn't that just a Porsche 911 GT3?
Not just any old 911, this is the Porsche 911 'GT3R Hybrid'.
Far removed from a Prius, Volt, or Insight, this Hybrid is a mobile laboratory for Porsche Motorsport as they develop Petrol-Electric Hybrid for road and race use. I was fortunate to see this new technology in action at Petit Le Mans, and with the help of John Brooks and Marshall Pruett of SPEED.com, we can look at the car in more detail.
The project started just under two years ago to support development of the Porsche 918 Spyder and Porsche Cayenne Hybrid SUV. The original plan was to run a Hybrid 911 at the Nurburgring 24 Hours, a race they almost ended up winning! More on this later.
Since then, Porsche have entered the car in to Intercontinental Le Mans Cup‘ races at Petit Le Mans and, next weekend at the Zhuhai 1000km event in China.
The heart of the Hybrid system is a Magnetically Loaded Composite flywheel, located where the passenger seat would be. This has been developed by the Hybrid division of Williams F1 team.
The hybrid system is separate to the normal 4.0 flat six engine.
The system creates an Electric charge under braking from the front wheels. This charge goes into a Power Converter unit, under the hood where it is converted from AC to DC.
This is sent to the Flywheel (above), spinning at 40,000rpm where it becomes Kinetic energy. The driver can then use this energy for 6-8 seconds of Boost before it needs to be recharged again. Itt can give as much as 160 horsepower boast! As this boost is fed to the front wheels, the car effectively becomes an All wheel drive machine, which is controversial in the motorsport arena!
The car may have more power and able to put that power down better, but the Hybrid system does cause a weight penalty of 150lb. Brake wear is reduced, but tire wear is increased at the front. As an unknown quantity, the ACO have placed this car in its own class as it neither fits in GT2 or GT3 (Its probably closer to a GT3 car really).
The balance of the car has also been changed. With the Power convertor at the front, the fuel cell was split with the second tank in the passenger footwell. Not sure if I would be comfortable having a flywheel at 40,000rpm and a fuel tank by my side….
Externally, the car looks similar to the Porsche 911 GT3-R racecar which was introduced at the end of 2010. Aside from the livery, additional air intakes on the rear fender are the most obvious change.
So, how did it do in Competition?
Manthey Racing ran the car on its debut in the German VLN championship, finishing sixth overall. A good start to the program, but everyone was surprised by its pace come the Nurburgring 24 Hours in May. As you can read on Speedhunters, the Hybrid almost won the endurance event. A valve spring in the ‘old-school’ engine failed with just two hours to go while in the lead.
Admittedly, the team had been lucky with a number of top entries falling out, but leading a 24 hour race is more than just luck.
BMW won the event, but most of the press centered on the 911 GT3-R Hybrid.
The Hybrid reappeared in September at Petit Le Mans, the finale of the American Le Mans Series and round two of the new Intercontinental Le MansCup.
The ALMS have been leaders in Green racing and promoting Hybrid racing, so it was only natural for the car to appear in this series. This wasn't the first time a Hybrid had raced in the ALMS. Back in 1998, Panoz and David Price Racing ran a Panoz 'Q9' Hybrid nick-named 'Sparky'. In recent years, Corsa Motorsports also ran a Zytek LMP Hybrid.
As a sign of how important this project is to Porsche, the team put the 2010 Le Mans Winners, Timo Bernhard/Mike Rockenfeller and Romain Dumas in the car, ‘borrowing’ from sister company, Audi. On this occasion, Flying Lizard Motorsport assisted with running the car.
The ‘all wheel drive’ system had an advantage during Wet practice at Road Atlanta, but come race day, in the dry, the car suffered from very heavy tyre wear.
The car eventually finished 18th overall out of 41 cars, which would have been 8th in GT2 class.
As Speedhunters’ Tommy Milner was racing the # 92 Rahal Letterman Racing BMW M3 at Petit, I asked him for his thoughts…. “The thing that stood out the most about that car was, when the drivers were using the boost, that thing was FAST. You'd be right up on the bumper of it and normally you could just hang with it but if they hit the boost, it would drive away from me like it was a P1 car it seemed like. It was pretty impressive. Otherwise the car seemed like it was somewhat competitive but not that close to us in terms of lap time. It never really factored in the race like I thought it would. It's strength must have come at the Nurburgring with its fuel economy and not really its outright speed. Although I'm sure it had built up enough energy to use on the Dottinger Hohe every lap.”
The action moves to Zhuhai next weekend for the final round of the Intercontinental Le Mans Cup.
As to the future, it is not clear if and when the Hybrid will run again, but one would assume the '11 Nurburgring 24 hourshas been penciled in. The ACO have not confirmed any Hybrid regulations for 2011, so if it did run again in the LMS or ALMS, it would have to run unclassified.
As a marketing exercise, this has ticked all the boxes with the car appearing on CNN, various new site, various green promitions and a number of magazine covers, but as an Engineering project, its is simply pioneering.
