Two Pedal Paradise- 911 Carrera S PDK

Only about 10 seconds elapse in our drive of the 2009 Porsche 911 Carrera S Cabriolet before we realize that we've just begun a love/hate relationship with Porsche's most brilliant piece of technology in the last 20 years — the Doppelkupplungsgetriebe, which, roughly translated, means "badass tranny."

Seriously, Porsche's PDK (Porsche Double Clutch) transmission — a new addition to the 911 model range for 2009 — is as spectacular at changing gears as it is awkward to use. This transmission has won our hearts with ridiculously quick shifts and immediate throttle response, but also doused our spirits with its frustrating interface.

Still, once you start winding corners together after adjusting to the shifting characteristics of the PDK, you'll quickly realize that the 2009 Porsche Carrera S Cabriolet's combination of newfound power and a best-of-both-worlds transmission enables it to satisfy the hard-core performance nerd and Newport Ned alike.

New Powertrain
An all-new 3.8-liter horizontally opposed six-cylinder engine with direct injection now powers Carrera S models. The new engine utilizes some of the same technologies as Porsche's previous mills (VarioCam Plus intake valve timing and lift), but the efficiency of direct injection and reduced engine friction allow it to produce an additional 30 horsepower and an additional 15 pound-feet of torque while consuming 12 percent less fuel (when the engine is matched with the PDK). This engine also manages to avoid the gas-guzzler tax and meet the EPA's LEV II emissions standard.

The best news, however, is that Porsche folks (especially those within Porsche itself) can now quit pretending to be fans of the Tiptronic automatic. Because it's gone, and good riddance. The PDK's seven gears and two clutches replace the five-speed Tiptronic's torque converter as the optional transmission (a six-speed manual is standard) for the 2009 Porsche 911.

Everyone will win, thanks to the PDK's flexibility. Those who care less about pure performance and want a Porsche because, well, it's a Porsche, will be thrilled with the PDK's ability to act like a smooth-shifting automatic. In fact, they probably won't even know the difference.

At the same time, the PDK's distinguishing feature is its ability to snap off shifts 60 percent faster than the Tiptronic and faster, in fact, than any human using a manual transmission, and those who relish pure performance will love this. The details are complex, but the speed is achieved by disengaging one clutch as it engages the other. Most impressive is the fact that tractive force (drive to the wheels) is never interrupted — kind of like an automatic transmission in a way, except without sucking. In comparison, there's always an interval in which a car with a manual transmission is effectively coasting, regardless of how quickly you move the stick and the pedals.

Two modes, Sport and Sport Plus, offer more aggressive calibrations for hard driving. Pushing the Sport button holds gears longer and increases downshift frequency under deceleration; Sport Plus calibrates shifts for the quickest possible speed and quickens response time to shift requests.

Hard-Driving Reality
So here's the catch. For all the PDK's flexibility and purposefulness, its interface with the driver is poor. First, the console-mounted shift lever must be toggled forward for upshifts and backward for downshifts. We've belabored this point before, but this strategy is just flat wrong. Upshifts should be as easy as pulling backward when accelerating and downshifts should come naturally by pushing forward under braking. Only BMW and Mazda get this right.

Then there are the shift buttons. The steering wheel buttons. Notice we didn't say shift paddles, because they aren't paddles, they're buttons — one two-way button on each side of the wheel. Push the front side of the button for upshifts and the back side for downshifts.

They're difficult to use. First, they're too small and in the wrong place. And it doesn't seem to matter whether we're trying to upshift or downshift, because we rarely manage to achieve the desired outcome. Maybe we're nitpicking here, since we'd eventually adjust to the function over time. But the placement and shape of the buttons are awkward at best and unusable at worst, and we found ourselves resorting instead to the console-mounted shift lever.

So What
Despite these criticisms, we still found the PDK stupefyingly good. And many people, we admit, won't feel as strongly as we do about which direction they push the lever or how hard it is to find the buttons.

There's no question that the PDK makes the 2009 Porsche 911 quicker than it would be with a manual transmission. And what's more, it's safer, too. Without the complexity of a third pedal, there's less to do when driving hard, so more of your attention can be focused on the other tasks, like picking a cornering line, nailing your entry speed and looking farther down the road.

And holy crap, is this Porsche ever good at those things. Magical steering, which manages to be precise and full of information without being jumpy or chaotic, has always been a Porsche strength, and the new 911 Cabriolet still has it. And the fact that there's no metal roof overhead only matters if you've ever wrung out a 911 with a solid roof. The compromise in structural rigidity is certainly apparent, but the driving reward doesn't take as big a hit as we were expecting. Really, this is an impressive driving machine with or without a lid.

Most striking is the power. Pour the coals to it coming out of a hairpin and the 911 is as composed and controllable as ever — it's just faster. Even without the optional limited-slip differential, this car is predictable and fun. And while it feels different from a front- or midengine sports car, the bite has been removed from its character and replaced by massive grip that makes fast driving effortless.

Banging gears with the PDK also has a satisfying feel not unlike the seamless power delivery of Ferrari's single-clutch F1 automated manual gearbox. There's also a distinctive sound that could only accompany a device as purposeful as this one.

The Straight Scoop
Despite this car's hefty curb weight of 3,510 pounds, the presence of increased power plus the PDK's launch control (part of the $960 Sport Chrono Plus Package) and shift speed make the Cabriolet quicker than the much lighter 2007 911 Carrera S Coupe. The Cabriolet hits 60 mph in 4.2 seconds (3.9 seconds with 1 foot of rollout like on a drag strip) and charges through the quarter-mile in 12.4 seconds at 111.8 mph. This is fast.

A large part of the PDK's appeal is that it's easy to access the launch control feature. Activation is simple: Push the Sport Plus button and disable the stability control via the PSM button, then mash the brake and wood the throttle — in that order. With revs held at about 6,500 rpm, the release of the brake produces the most carefully managed acceleration we've ever experienced. Remarkably, there's no wheelspin.

All the torque that isn't turned into acceleration goes straight into the 1st-gear clutch pack, which makes the PDK's ability to resist heat soak even more remarkable. The PDK never shows any sign of overheating and defaulting into safe mode. In fact, Porsche engineers tell us the PDK can handle 40 launch-control hits back to back with no ill effects.

Can You Handle It?
In the slalom, the Cabriolet cranked out only 68.8 mph, something we blame on the convertible's inherent compromises in structural rigidity since the 2007 911 Coupe was 2 mph faster.

Grip, however, was higher at 0.93g. This is largely due to the front 235/35ZR19 and rear 295/30ZR19 Michelin Pilot Sport rubber. The handling balance tends toward understeer, and even large stabs at the throttle don't produce ugly oversteer. Physics, it seems, no longer applies at Porsche.

This Carrera S Cabriolet's braking performance is equally awesome thanks to 13-inch rotors and four-piston fixed calipers, which haul this car down from 60 mph in 102 feet.

Is That Newport Ned?
So this car is capable and fun, and it's likely to satisfy those who enjoy driving. And if you just like the whole Porsche thing, this car truly nails it.

Tap and hold the button that operates the soft, convertible top and 13 seconds later you'll have full exposure to the elements. We'll also admit that this Cabriolet has options like cocoa-color natural leather ($4,085), navigation ($2,110), a Bose sound package ($1,440) and even a heated steering wheel ($190). Add it all up and we're reminded why Porsche can easily be called a luxury and performance brand. In the timeless words of editor Oldham, "Nice stuff is worth paying for."

To be honest, this is about as elegantly constructed as an automobile interior can be. Only the design gives us pause, as the center stack is filled with buttons, which complicates the operation of some features.

Is It Worth It?
With $22,175 in options, this 2009 Porsche 911 Carrera S Cabriolet proves that Porsche makes much of its revenue from customers who like to check boxes on the order form. Including destination, this car rang up a price tag of $119,925.

Whether this sports car is worth this kind of money probably depends on two things: your net worth and how much you love Porsche's new badass tranny.

Summing Up-

What Works:
Striking power and speed for a normally aspirated Porsche; brilliant transmission performance.

What Needs Work:
Awkward transmission interface; cacophonous idle noise; too 'spensive.

Bottom Line:
A brilliantly engineered, masterfully executed, highly engaging sports car — which is still better with a top.

By Josh Jacquot, Senior Road Test Editor Email | Blog
Date posted: 12-17-2008