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Porsche 991: our comprehensive guide to the new 911
Ben Barry (photography exclusively for CAR by Paul Barshon)
First Official Pictures
12 October 2011 16:46
3. Porsche 911's seven-speed manual gearbox
The 991-era 911 showcases the first seven-speed manual gearbox in a production car. Despite being a manual, it actually shares much with the PDK transmission and comes down the same production line. Even the ratios are largely the same, save for a taller third and slightly shorter seventh cog. Did these commonalities result in any compromises? Not really, says R&D boss Wolfgang Hatz. He tells us that the distance between the engine and the axle is the same as for the previous 911, despite the changed gearbox that lies between them, and that the weight of the two units is identical. ‘Perhaps,’ he says, ‘we could maybe have it lighter if we’d made a “pure” manual seven-speed.’ Did the team ever consider not offering a manual gearbox at all? ‘No,’ he says firmly. Both the manual and PDK come with a stop/start system to automatically shut off the engine at traffic lights.
IN A NUTSHELL The world’s first seven-speed manual in a production car.
4. New Porsche 991's PDK transmission
The seven-speed PDK returns for duty in the 911, but this time there’s a twist: a ‘sailing’ mechanism. Brake gently or back-off the throttle lightly and the engine de-couples from the transmission, reducing fuel usage. Make harder inputs and the mechanical connection remains in check, ensuring a keen driver gets the suitable amount of engine braking. It is, promises Hatz, incredibly subtle. ‘When you are cruising at 90mph the engine noise is very low anyway, so you don’t hear or feel it,’ he says.
The controversial rocker paddles (pull either paddle to change down a gear, push either paddle to change up) return to the 911’s steering wheel and, once again, you can opt for a more conventional set-up (left paddle for down, right for up). However, there is a catch: the conventional paddles can’t be paired with a multi-function steering wheel. ‘We’re working on it,’ says Hatz.
IN A NUTSHELL Engine and PDK transmission decouple to save fuel.
5. The chassis of the new 991
‘This car is 100% new with a completely new platform,’ says Wolfgang Hatz. ‘It’s a big investment.’ Perhaps the biggest change to the new 911 is the extra 100mm that’s gone into the wheelbase, shorter overhangs ensuring the overall length has grown only by 56mm. Elsewhere, the 911 is no wider, but it gets an entirely new rear axle and a wider front track (48mm for the Carrera, 52mm for the S). The aim is to improve comfort and stability, but purists will surely worry that the longer wheelbase will impact on the famous 911 agility.
‘People say a shorter wheelbase is more reactive, but that’s not the case here. Turn this car in and it goes…’ says Hatz, shooting both his hands off down an imaginary road. ‘In the old car you were always… [moves hands up and down on an imaginary wheel] but here at 150mph you can take your hands off the wheel.’
There are new toys too: Porsche Dynamic Chassis Control largely eliminates roll without impacting on comfort because hydraulic actuators de-couple the anti-roll bars when the car isn’t cornering. ‘Roll?’ asks Hatz, ‘You don’t feel it anymore.’ Meanwhile, Porsche Torque Vectoring combines with a limited slip differential but is more predictive than the traditional reactive diff – sensing slip is about to happen in a corner, it subtly brakes the inside rear wheel. The familiar Porsche Active Suspension Management adaptive dampers are also tweaked. Says Hatz: ‘There’s a much broader spectrum from comfort to super sporty.’
IN A NUTSHELL Wheelbase longer by 100mm, but there’s no loss of agility, promises Porsche.
>> Click 'Next' for the design story of the new 991-spec Porsche 911