Weissach is busy. There might be a global pandemic on, but that hasn't stopped the Porsche Development Center engineers from working on new models. One prototype Porsche 911 GT3 leaves through the gates as I wait at the visitor reception, the body-covering “disguise” fooling nobody – the most focused 911 has been the darling of spy cameras for the past 12 months or so.
Merely spotting one would usually be something to get excited about, but today's different, as I'm sitting shotgun in one of those GT3 prototypes with Porsche's GT boss, Andreas Preuninger, behind the wheel.
Preuninger and his team are putting a fleet of prototypes through final validation as of this writing, all in a final effort to hone the details of the production car ahead of its 2021 on-sale date. The charismatic boss is taking a break from that work to chauffeur me about as I fire questions at him. We've known for a while what's going to be powering the new GT3 – a development of the naturally-aspirated 4.0-liter flat-six found in the 991.2 Speedster.
There are changes to the engine, says Preuninger, but they're centered around making what's essentially a racing engine pass road car regulations. For example, the emissions-reducing exhaust particulate filter created an engineering challenge for the GT3 team.
There are changes to the engine, says Preuninger, but they're centered around making what's essentially a racing engine pass road car regulations.
“If you clog up an exhaust with big catalysts and take a big [particulate filter], that's initially a problem, because an engine is an air pump – air in, air out,” says Preuninger. “If the air doesn't come out, we have a problem. We have to counterbalance that with compression, with intake, with timing. Timing on the other side is very sensitive to emissions as well. You really have to find your way through the maze to get the best results.”
The best result here? The same 9,000-rpm redline and 510 horsepower as the Speedster and 10 hp more than the previous-generation GT3. It's plenty. It sounds pretty special, too, with a bassy, rich timbre at low revs changing to a rousing shriek when reaching that red hash on the tachometer, Preuninger wringing it out as often as is possible on roads he's familiar with. North American cars will likely even sound better, as the particulate filter Preuninger mentions isn't required and hasn't been found on the broader 992 family.
An 80/20 Proposition
Preuninger admits that some 80 percent of his team's engineering efforts focused on just getting the GT3 to pass the countless global regulations – be it emissions, noise, consumption, crash and more – to allow worldwide sales, with the remaining 20 percent of brain capacity dedicated to upping the ante.
Doing that while pushing out much the same power means a greater focus on the chassis and aerodynamics, Preuninger talking of efficiencies in all areas to improve the GT3's performance. The usual barometer of that is a Nurburgring lap time, but he's not prepared to discuss that in detail today, saving that number for the GT3's launch. He wryly concedes that there'll be a decent improvement over the previous car, though.
Preuninger admits that some 80 percent of his team's engineering efforts focused on just getting the GT3 to pass the countless global regulations.
Preuninger's happy to talk other numbers associated with the 992 GT3. One of those he's clearly pleased with is that there's no increase in weight over the 3,116-pound 991.2 GT3, despite the 992 platform being significantly heavier in Carrera guise and bigger overall. The GT3 achieves its mass reduction by the usual methods, with polyurethane front and rear bumpers, thinner glass on all but the windshield, removal of sound deadening materials, no rear seats, and lighter materials wherever possible.
There's a carbon fiber bonnet that needed extensive work to allow it to pass pedestrian crash regulations. That's just one example of where that aforementioned 80 percent of effort goes.
“The whole process of developing a car has gotten so complex,” says Preuninger.
That's particularly true in relation to something as singular in its focus as the GT3. It's why most rivals have gone turbocharged or hybridised, something the GT department is keen to avoid for as long as possible.
As much as it obviously frustrates, that challenge is evidently also one that Porsche relishes. Making the GT3 faster, more precise, and enjoyable, then, is about efficiency as much as it is anything else. Aerodynamics are key – the 992 GT3's enhancements provide 50 percent more downforce without any increase in drag. Managing the air around the front, underneath, and crucially, the rear is central to that.
“It's form follows function, always, especially [with the rear wing] – the race cars all have hanging wings because the suction side (the underside) is as important, actually even more important than the side on top where the pressure is applied,” Preuninger says, adding the rear spoiler even cleans up airflow into the engine bay.
“I don't want a slow car on the autobahn. When up at 150 miles per hour, I don't want the car running against limits because of the wind resistance. It has to be quick at acceleration, even at higher speeds.”
Up front there's a wider splitter that directs air where it's needed, providing both cooling and aero stability while a significantly larger diffuser underpins the rear wing. Taken in sum, the racy additions grant the GT3 its huge leap in downforce while retaining the low drag that Preuninger requires.
“We live in Germany,” he says. “I don't want a slow car on the autobahn. When up at 150 miles per hour, I don't want the car running against limits because of the wind resistance. It has to be quick at acceleration, even at higher speeds.”
Usefully, our route takes in a section of derestricted autobahn, and Preuninger takes the opportunity to ably demonstrate the GT3's high-speed acceleration, as well as its obvious stability.
The Right Parts Bin
Off the autobahn and on more challenging country roads is where the GT3 really comes alive, though. What's very apparent is the quality of the ride, the suspension juggling that difficult trick of precise control allied to a compliant, supple ride despite a 25-percent increase in spring-rate stiffness over the outgoing car. The damping is key here, with Preuninger and his team spending countless hours tuning it.
That's even more impressive when Preuninger admits there are no elastokinematics in the suspension. The rear setup is largely carried over from the 991.2 GT3, so it's multi-link with rear-wheel steering. It's the front axle where there have been wholescale revisions. There's a set of forged aluminium wishbones there, replacing the more usual MacPherson struts of the 911.
Those wishbones come from the same parts shelf as Porsche's race cars, their fitment fundamentally changing the front of the GT3.
“Race cars almost always have double wishbones,” Preuninger says. “We were not sure if we could get this system to work – it was a big discussion and a big problem to solve. But we did it, and it was worth it.”
Those wishbones come from the same parts shelf as Porsche's race cars, their fitment fundamentally changing the front of the GT3. Quicker to react to bumps, there's less friction in the suspension, while the dampers can be lighter since they no longer have to cope with braking forces.
“[The wishbones] called for a completely different approach on the steering as well,” according to Preuninger. “We had to start from scratch – there are different resistance values in the front axle. It's the same hardware, but it reacts differently, because the forces it encounters when turning the wheel are far different.”
He says there's still lots of feel, and from the passenger seat it's evident that turn-in is quick and accurate. The boss demanded the GT3 feel entertaining and rich in detail at any speed, not just higher ones.
Preuninger demanded the GT3 feel entertaining and rich in detail at any speed, not just higher ones.
The wheels hanging from that suspension are bigger – 20 inches in diameter and 9.5 inches wide up front and 21 inches across and 12 inches wide in back. They're wrapped in Michelin Pilot Sport Cup 2 tires with a staggered section width of 255 and 315 millimeters. The brakes have grown in size too, with the front discs being 16.0 inches and the rears 15.0. They're pitted rather than through-drilled, in another nod to the racing cars, and Porsche ceramic composite brakes will be available optionally, too.
Living Up To Expectations
In the stripped – but not stark – interior, there's GT3 specific instrumentation with shift lights arcing around the central rev-counter, while the multiple drive modes of a standard Carrera have been reduced to just three in the GT3. There's Normal, Sport and Track, each configurable to change things like the exhaust, Porsche Active Suspension Management, and stability and traction control systems. On GT3s fitted with the PDK dual-clutch transmission, the drive mode selector will also adjust gearshift mapping.
That seven-speed PDK gets paddles as well as a large transmission tunnel-mounted shifter (it's there because Preuninger prefers changing with the shifter). Manual fans can have a six-speed transmission and three pedals on both this regular, winged GT3 as well as the more subtle Touring.
As the chief engineer says, “The GT3 is a motorsport car so it has to live up to that expectation, the emotion and the fun to drive the car, the urge to sit in it, to go for it, to take it for a spin, that's the important thing. That's what makes the people want the car from the heart to the stomach. That's definitely the main driver, to be driving for the sake of it.”
Our early ride in the prototype underlines that, because after sitting in the wrong seat all day, we can't wait to try it out from the right one…
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