Porsche 911 GT3 (997)
The new GT3 is a more sophisticated animal, so has it lost its bite? We put it through its paces on road, track and dyno to find out
Looking at the specification and options for the new GT3, you might think it has gone soft. Standard kit includes adaptive damping, air-con and traction control, to which you can add satnav, electrically adjustable leather sports seats, a sunroof, cruise control… You might even be tempted to think of it as a Carrera S with a bodykit, stiffer suspension and a bit more power. You might be wrong, of course.
The GT3 is a product of Porsche Motorsport, and is the ‘entry level’ model in a four-model line-up that also includes the GT3 RS and two race cars, the GT3 Cup and GT3 RSR. The first three are built on-line at Zuffenhausen, while the 3.8-litre, 480bhp RSR is built by the racing car department at Weissach.
Riding on bespoke, semi-slick Michelin Pilot Cup or Pirelli Corsa tyres, the differences between the GT3 and the regular Carrera start literally from the ground up. In effect it is an homologation special, a car designed and developed with the motorsport aspirations of the racing GT3s in mind, and this influence goes to the core of its structure and penetrates the very heart of its flat-six engine.
All GT3s are built around the floorpan of the four-wheel-drive Carrera 4, partly for the extra stiffness its transmission tunnel confers and partly because the front end, minus the differential, allows the fuel tank to be mounted lower. The bonnet and doors are made of aluminium, the engine cover of a plastic composite, and Porsche’s engineers claim that, compared with the 996 GT3, the new model is eight per cent stiffer torsionally (corner to corner), and 40 per cent stiffer flexurally (front to rear). And that’s for a car that, like for like, weighs 5kg less than the 996 GT3, though to gain that advantage you have to take up the no-cost-option deletion of air-conditioning, whose gubbins add 20kg.
I doubt that Porsche received any complaints about the power and response of the 996 GT3’s 375bhp flat-six, but for the new GT3 the naturally aspirated 3.6-litre engine has been subjected to a meticulous, obsessive drive to reduce internal masses. The short-stroke, dry-sumped boxer six now revs to a maximum of 8400rpm, 200rpm higher, and with the help of a mild ram-air effect from the engine-cover air scoops, a larger intake butterfly and a compression ratio up from 11.7 to 12.0 to one, it develops a heady 409bhp at 7600rpm. That gives it an exceptional rating of 114bhp per litre and makes it almost as powerful as the twin-turbo 3.6 fitted to the 996 Turbo.
Yet it is also a very tractable engine and, of course, meets EU4 emissions standards. New to this latest GT3 engine is VarioCam, which adjusts the intake cam timing and thus helps improve both efficiency and the spread of torque. Meanwhile the exhaust system is essentially the one developed for the GT3 Cup racers, though ahead of the large-volume main silencer is a pair of ‘pre-silencers’. These feature bypass valves that open up to lessen back-pressure at pre-determined engine loads and speeds.
Also new to the GT3 are adaptive damping and traction control. On its regular setting, PASM (Porsche Active Suspension Management) is said to give a similar feel to the passive set-up of the previous model, but with the added benefit of a selectable, firmer mode for smooth track work. Traction control (TC) bolsters the GT3’s mechanical locking differential, which provides 28 per cent lock-up under power and 40 per cent on the overrun. TC is based on the system from the Carrera GT and steps in when wheelspin becomes excessive. It also acts to limit engine-braking on the overrun to prevent locking up of the wheels on over-ambitious downshifts. It can be switched off.
Tick the ‘Clubsport’ box on the options list and, at no cost, the GT3 is supplied with a battery master switch, fire extinguisher and six-point harnesses. It will also be fitted with a half cage, which must add further rigidity – manoeuvering on lumpy ground you occasionally hear it ping, like a chromed seat-belt buckle has chimed lightly against it. You can, of course, add considerably to the GT3’s £79,540 list price if you wish. PCCBs (Porsche Ceramic Composite Brakes) cost £5800 and save 20kg, while Carrera GT-style carbonfibre-shelled bucket seats weigh just 10kg each and cost a staggering £3130 a pair. All of these options are fitted to our test car, which, finished in plain white, looks as though it is just awaiting sponsors’ logos and number roundels.
Even without them it exudes a wonderful purity of purpose. Low, lean and with its dry-road-biased rubber cramming the arches. While the RS and the racers use the Turbo’s wider rear arches, the regular GT3 is skinned with the slimmer-hipped Carrera 2 panels, helping it to a drag coefficient of Cd 0.29, a point lower than the RS. That’s a remarkable result given the number of air scoops, slots and vents that gulp and exhale, and that front splitter and two-tier rear spoiler that help generate stabilising downforce.
An engine with a high specific output will be powerful and economical, and the GT3’s certainly is. On a gentle motorway cruise to South Wales for photos, we saw an astonishing 30mpg. Yep, 30mpg. Naturally, we managed to beat that down a bit while we were there, and then got it right down at Millbrook and the Bedford Autodrome. At one point the trip computer was promising a range of just 50 miles from half a tank (33 litres) of super unleaded…
The early miles are a reminder of the instant appeal of the GT3. You get the sense that there isn’t a micron of slack or an ounce of fat in it. The precision and weighting of the controls is near perfect: the powerful brakes bite right from the top of the pedal yet are progressive, the short-throw gearshift has such a direct, mechanical action that you’d swear the cogs were beneath the lever, and the steering brims with feel, conveying the texture of the road even in a straight line.
The big surprise is the ride quality. Body control is taut yet the suspension is remarkably absorbent, smoothing out finely rippled, pocked surfaces that you expect to induce fidget and fuss. We did find the worst road in Britain, though, with a pronounced crown, countless manholes and multiple raised ridges of asphalt from hastily filled-in pipe excavations. This was too much for the GT3, which jinked all-of-a-piece from one blemish to the next, its nose tugging this way and that. Mostly, though, even this classic 911 trait seems to have been subdued, and the GT3 is generally so composed that you’d think the front axle was carrying more of the load.
As you’d expect, however, when the chance comes to push on, the GT3 delivers a rich, full-bodied 911 experience. The engine is a masterpiece, plenty tractable enough in the low- and mid-range for the gearing not to feel over-long, but revealing a thrilling, epic reach when you keep it nailed. The smooth-spinning six’s mid-range bellow becomes a thinner, almost manic howl beyond 5000rpm, and by 6500rpm the push in the back is so insistent, the yowl of the flat-six so urgent, that you can’t imagine it getting any better. But it does, kicking again at 7000rpm and lunging for the 8400rpm limiter.
On a dry road the grip is astonishing, yet that’s just a part of the experience. Beneath you is one of the finest 911 chassis yet, one that engages and challenges. You’ve got to drive the GT3, though; read the road, feel what the beautifully weighted, sensitive steering is telling you and judge when to apply the power on the exit of a corner. You’re always aware that the bulk of the weight is behind you. Occasionally you can imagine an inside front wheel clear of the deck, and it feels marvellous.
In the dry, breaking traction is a rare event, but understeer can build if you don’t work around it, a characteristic that is exaggerated in the wet on the Cup rubber. Find a slippery corner on an otherwise dry road and you can see understeer and oversteer before you’ve seen the apex; in a downpour you’ve got to tread very warily because the traction control seems to intervene only when you’ve already wound on opposite lock.
Will it do the numbers? Well, it’s a Porsche, which in this business is as close to a dead cert as you’re going to get.
With some 62 per cent of its weight resting on its rear wheels, traction off the line isn’t a big issue, but getting the absolute best start takes just the right revs. Dropping the clutch with between 2600 to 2700rpm dialled up works best. The rear end judders as the tyres slip/grip rapidly for a few metres before hooking up fully with the revs now sitting at 4000rpm. From that point the flat-six feels like it has its shoulder right behind the weight of the car and shoves it forward with an escalating, intoxicating urge.
The numbers are impressive: 60mph comes up in 4.3sec and 100 in just 9.4sec. However, Porsche’s metric claims are 0-100kph (62mph) in 4.3 and 160kph (100mph) in just 8.7sec, so we’re more than a few tenths adrift of the latter. It also means that the 996 GT3 we tested back in issue 060 isn’t put into the shade – it recorded the same 0-60 time and hit 100 two tenths quicker at 9.2sec. Both models nail the quarter mile in 12.5sec.
Intriguingly, although the gear ratios of the new car are said to be shorter than the 996’s, it seems that the engine’s extended rev-range gives it almost the same reach in every gear. Both GT3s hit the same increments and return virtually the same in-gear figures. And excellent figures they are too: in second gear, 40-60 and 50-70 take less than two seconds, which, not to get too technical, is the rate at which your average passenger will either wet themselves or swear out loud, laugh and ask if you can do it again. Third gear especially shows how the mid-range muscle is created and sustained with exhaust valve, intake tract and VarioCam shifts, all the way through to 8000rpm.
From the mile straight, we move to the high-speed bowl. Within two-thirds of a lap the VBOX’s digital readout is showing over 160mph. All feels well. I nail the throttle again, but as we hit 170mph approaching the bridge, my right foot wavers. The GT3 feels utterly stable and the engine just wants to go for the limiter in top, but I don’t. It’s still damp on this section and we’re on semi-slicks.
We take to the damp at 155mph. Not much changes, but what warning would you get if it did? We’re still cornering hard, pulling around 1.1 lateral g, the VBOX later reveals. I squeeze on the throttle as we approach the dry again and the urge from the flat-six is superb. Well before the bridge comes around again we’re at over 180mph on full throttle, pulling 1.3 g, with the front splitter lightly grazing the track over the biggest bumps.
Sadly the track didn’t dry, preventing flat-out laps, so the peak speed we managed will have to serve as an indicator. It was 181.4mph, easily the fastest I’ve been around the bowl and the fastest car evo has ever lapped there. I don’t doubt that with a couple of laps to wind up to it, the GT3’s final average could have been 185mph, entirely consistent (taking scrub into account) with Porsche’s claim of 192mph.
Unfortunately, the West Circuit has been modified since we lapped the 996 GT3, so we can’t compare lap times. However, we do have current times for the 996 GT3 RS and the current 911 Turbo. Our pre-flight involves selecting Sport mode and stiffer PASM damping but, initially, leaving traction control engaged. As it turns out, when you select Sport the grip of TC is loosened enough to make its interjection a last- ditch, you’ve-ruined-the-lap-anyhow affair, so we quickly dispense with it.
There’s huge grip from the Cup tyres and the rears don’t seem to overheat like regular road tyres do on the back of other 911s, Turbo included. They break away progressively, too, yet to get a good time from the GT3 you need to be very precise with your corner entry. Come in too hot on the brakes and you’ll be grappling with time-wasting oversteer; try to get the power down too early in the slower corners and you’ll be reining in understeer.
Happily, the ceramic brakes are powerful and fade-free, and perfecting your lines is utterly absorbing – get a corner just right and you know it. Thing is, though, if you’re driving on track simply for fun, the GT3 is wonderfully benign. It falls into oversteer progressively and comes back into line just as cleanly, so even big slides are collectable, while the precise delivery and reach of the engine give you options too. I eventually put in a good, clean lap, which is a relief because we have an appointment at the rolling road. The time of 1:23.40 makes it a fraction quicker than the Turbo and also a few tenths faster than the 996 GT3 RS.
Any doubts that the GT3’s engine is producing the full quota of horsepower are dismissed in less than five minutes on the WRC dyno. Within three runs the engine produces two back-to-back figures within 1bhp, and the result is 429bhp. That’s almost 120bhp per litre. WRC has tested a few GT3s and GT3 RSs and say it’s spot-on for a GT3 fuelled with 99 octane Shell V-Power.
VerdictThe 997 GT3 certainly hasn’t gone soft. It’s one of the best drivers’ 911s ever – fantastically tactile, irresistibly engaging and fitted with one of the most thrilling flat-sixes Porsche has ever built. Far from detracting from the experience, the standard fitment of adaptive suspension, traction control and air-conditioning all add to its appeal – PASM allows it to be more sporty on track, TC offers a (switchable) safety net, and 20kg is a modest penalty to pay for the benefits of air-con.
In fact, the fitment of lightly treaded ‘trackday’ tyres makes it the most uncompromising GT3 there has been. Dry-road grip is exceptional, but in the wet you’ve got to tread very cautiously. Yes, you can specify it with creature comforts such as satnav and electric seats, but don’t ever imagine it’s merely a sportier Carrera S. The GT3 has teeth, and it will bite.
|Engine||Flat-six, 3.6 litre|
|Max power||409bhp @ 7600rpm (test car 429bhp)|
|Max torque||298lb ft @ 5500rpm (test car 315lb ft)|