Porsche predict a future for hybrids in endurance racing
A conventional 473bhp flat six powers the rear wheels...
...while regenerative electric motors push 160bhp through the front
Three laps with hybrid mode engaged were astonishing
Straights disappeared much more quickly with electric drive engaged
A short period of havy braking recharges the flywheel
Magic button releases up to eight seconds of boost
Regenerative system much more effective than F1's KERS
Technology needs further development before it's ready for road cars
What is it?
Right now, the GT3 RH is still just a racing-cum-test development program, a toe in the water regards Porsche’s future road car development plans. But be in no doubt, it’s also a very loud, very clear, slightly scary example of the way in which Porsche is thinking right now when it comes to power-trains. Hybrids, if this monster of a machine is anything to go by, are quite clearly the future for companies like Porsche and Ferrari et al.
As the GT3 RH’s chief race engineer, Owen Hayes, puts it: “I regard the whole hybrid thing a bit like mobile phones from 20 years ago. Some people said they would never catch on but look where we are now. For endurance racing in particular, that’s exactly how I feel about hybrids.”
And for road car use? “What’s not to like about hybrid power for high performance road cars in future, even if there is still some way to go right now. Ask me in five years time…” he beams, with a great big grin across his face.
So what sort of machine are we really talking about here, and how is it likely to influence Porsche’s future road car development? In simple terms the GT3 RH uses a conventional 473bhp flat six engine mounted at the back, powering its back wheels, while over the front axle it has a further pair of 60kw electric motor that power the front wheels, each developing 80bhp. Which means it has 633bhp in total.
The system works by generating power primarily via the car’s brakes, and it then stores this power in a whopping great flywheel that sits abut six inches to the right of your backside. And when you press the magic button, with the flywheel spinning at up to 40,000rpm, it then redeploys the stored power back to the front axle wheels and, presto, you get a monster great hit of acceleration for 6-8 seconds – perceptible in any gear, and at any speed.
The really clever bit, though, is that it generates its power almost exclusively via the brakes, not via the engine or a bank of batteries, as in the 2009 F1 systems. And this means it can regenerate full power almost as fast as you can burn it. One big stop from sixth to third gear and you can virtually recharge the system – and that makes it much more efficient than the KERS that was used in F1.
What’s it like?
Quite spooky, incredibly efficient but also just very, very exciting to use. When you press the magic button for the first time it actually feels a bit like a cheat, the rush of extra acceleration comes at you that fast. But when you get used to the way it works – the way it can alter not just your speed along a straight but also the handling balance mid corner even – the hybrid GT3 R is quite clearly a highly significant piece of kit; the beginning of a brand new era.
In practice, the system recharges so fast that it is constantly available, simply because unless you forget to press the brakes for some strange reason, you are always recharging the system. So it’s a win-win situation, except for two things.
One, weight; all up the system adds 150kg to the weight of a regular GT3 R (1200kg). Two, at the moment the only way to ensure that a proper recharge takes place is to brake very hard indeed. Use the brakes like you would on the road and, as it stands, the system wouldn’t recharge properly, which can cause all sorts of overheating issues.
Even so, it’s hard not to be impressed, no, to be blown away by the way this car performs. The ease with which the system generates and then gives back its power is genuinely incredible. Once Porsche works out ways to reduce the weight of the system – and that’s purely a matter of “time, money and engineering effort” according to Owen Hayes – there will be almost nothing not to like, and lots to get very excited indeed about hybrid power.
In the end they gave me six laps in the car, three with the hybrid system off, three with it on. On laps one, two and three I drove fairly hard and enjoyed the GT3 R for what it is; one of the most successful cars in modern GT racing. It was faster and more brutal than I was expecting in some ways, more delicate and touchy-feely than I had anticipated in others.
And then they hung a sign out over the pitwall that read “hybrid, push.” So I did, and that’s when the magic started.
I could tell the system was fully primed because, during the previous three laps, a row of green Christmas tree lights had gradually started to illuminate on the left hand side of the dash. At the same time my passenger – that huge flywheel, the motor – had started to make louder and stranger noises; it sounded like some kind of crazed hoover that was spinning faster with every second.
The first time I pressed the button, half way along the main straight, it really did feel like an extra 400lb ft had been instantaneously released. The GT3 didn’t so much leap forwards as appear quite a lot nearer towards the end of the straight. There was no great audible change of timbre, except for the fact that the revs rose faster than previously. It felt literally like some enormous unseen hand had attached itself to the back of the car and given it a great big shove.
And the amazing thing is, it’ll give you that same intensity of boost, the same dramatic thrust towards the horizon along almost every straight, and out of every corner – so long as you hit the brakes hard enough in between.
Should I buy one?
You can’t for the time being because this is the one and only GT3 R hybrid in existence. No matter, because hybrid power is not the future for companies like Porsche and cars like the 911, it is the present. Not so much the end of the road for high performance cars, but the beginning of a brand new chapter.