Doppelkupplungsgetriebe! New transmission sends 911 into overdrive

Stuttgart, Germany—Whenever the assignment is to drive latest generation Porsche 911, there’s no question over whether the car will be good or not. It will be good. It will also represent an incremental improvement over the previous model. So, for the most part, the story writes itself—plug in the new horsepower and torque figures, apply some superlatives and you’re good to go.

On the surface of it, this should have been the case with the 2009 Porsche 911 Carrera and Carrera S. Both have received a requisite boost in output, mainly due to the incorporation of direct fuel injection: the former’s 3.6-litre flat-6 delivers 254kW (345 bhp) and 390 Nm of torque, the latter’s 3.8-litre version produces 283 kW (385 bhp) and 420 Nm of torque.

The new Carrera 911 also sports some exterior changes to its still-iconic shape: a revised front bumper, larger air intakes, larger side mirrors, daytime LED running lights and a vastly different LED brake light treatment. Other revisions include larger standard disc brakes, wider rear tires, a revised suspension system, optional sports suspension with the Porsche Active Suspension Management adaptive damping technology, a touch screen-operated navigation system, a dedicated iPod interface and ventilated seats.

But all of the above pales in comparison with the key development in the new 911—the Porsche-Doppelkupplungsgetriebe, dubbed PDK for short, the company’s revolutionary new dual-clutch transmission.

Now, make no mistake: I’m as pure as a purist can be. I’m all about the manual transmission, particularly the type found in sports cars such as the Porsche 911. Six forward speeds, a weighty clutch, a short-throw shifter and the distinct pleasure of a well-executed heel-and-toe downshift. Magic, pure and simple. I love the manual transmission and I’m not yet prepared to mourn its inevitable demise (I give it five years, max.) But while I thoroughly enjoyed my time behind the wheel of the Carrera S fitted with the 6-speed manual, the optional 7-speed PDK, I quickly learned, is capable of whole new levels of trickery.

As with most things Porsche, this slick bit of tech has come straight from the track. First seen on their 956 race car in 1983, the PDK transmission has since been fine-tuned to suit the discriminating tastes of the average Porschephile and to deliver shifts in a fraction of a heartbeat.

In racing parlance, the term “shift without lift” means to change gears while keeping the accelerator pedal flat to the floor. This, in turn, means quicker acceleration and no hesitation between shifts—in other words, no punches to the kidneys every time you take the next highest gear while traveling at a real clip. In other words, the engineers at Porsche should’ve labelled their new transmission “PDQ” instead.

It’s pretty damn cool, too, apart from the shift buttons. While almost every other manufacturer opts for the de rigeur shift paddles—also derived from racing—Porsche is determined to try to convince people that buttons are better. Perhaps when minivans begin to sport paddle shifters, they’ll change their tune. Let’s wait and see.

Back out on the autobahn, the Carrera S lived up to its promise. Scrolling up through the gears, the flat-6 kept right on motoring towards its theoretical top speed. The digital readout set within the analog speedometer told the tale: 200 km/h… 220… 240.

Drops of rain appeared on the windshield, but the Porsche held fast to the surface of the smooth pavement. This served to highlight the reasons why cars like the 911 are so expensive: a shape that carves through headwinds and resists crosswinds, steering that communicates the slightest variances in grip, tricks like a rear spoiler that automatically deploys to increase stability. This all costs money—and so, too, does a sports car capable of venturing beyond 240 km/h to 260 and then 280. (You get the picture.)

At 280 km/h, 30 kilometres of road gets chewed up in a big hurry. So when a road sign warned that our exit was fast approaching, it was time to dispense with thoughts of hitting that theoretical top speed (300 km/h), bring the optional ceramic composite disc brakes into play (like pulling the rip chord on a parachute) and make a decisive move to the right. But when confronted with a long line of trucks all jockeying for position, it was also time to pull one last trick out of the PDK bag.

I slotted the central gear lever into the fully automatic position and the transmission duly picked seventh gear: overdrive. I pinned the accelerator to the floor and the transmission automatically dropped down to second in less time than it takes your heart to emit a slow beat, a process that takes as much as two milliseconds. Thus engaged, the Porsche sprinted ahead of the pack, merging into the exit lane with ease. (Now, it’s no huge feat to pass a line of trucks with a Porsche, it’s just the way this Porsche passed that line of trucks—so quick, so effortless.)

Whenever the assignment is to drive latest generation Porsche 911, there’s no question over whether the car will be good or not. It will be good. It will also represent an incremental improvement over the previous model—in the case of the 2009 edition, this means more power, more torque, better fuel economy and reduced emissions.

But every once in a while, the latest generation Porsche 911 will also represent a major leap forward from a technological perspective—this is that time and the PDK is that technology. All things considered, impressive is too tame a word.