The Complete Book of Porsche 911
Page 23
FINAL DRIVE AXLE RATIO
3.44:1
TOP SPEED
180mph
PRODUCTION
1,963
2004 Ruf RGT RS Coupe
Ruf installed a full roll cage inside the car. Through liberal use of carbon fiber body panels, he brought his car’s weight to 1,359 kilograms, 2,990 pounds. In homage to the original 1973 Carrera RS, Ruf added a fixed ducktail spoiler. Photograph © 2011 David Newhardt
Acceleration from 0 to 100 kilometers took 4.1 seconds. Fender flares front and rear slightly increased wheel track, improving handling. Rear tires were 315/30R18s. Photograph © 2011 David Newhardt
By revising the intake, creating a new exhaust system, and reconfiguring engine management programs Alois Ruf’s engineers developed 395 horsepower from the normally aspired 3,600cc (219.6-cubic-inch) GT3 engine. Photograph © 2011 David Newhardt
CHAPTER 8
THE SIXTH GENERATION 2005–ON
2005-2008 CARRERA
2005-2008 CARRERA
2006-2008 GT3
2007-2010 911 TARGA AND CARRERA
2008-2009 GT2
2008-2009 911 TURBO
2010 GT3
2009-2010 TURBO
Porsche switched up the development order with the 997. Weissach started with the convertible, knowing the lineup would include it, and then went to work on the coupe. “This strategy came from the engineers’ point of view,” August Achleitner explained. “The convertible is more difficult because of the stiffness that is necessary.” Achleitner was Porsche’s director of product line management for the Carrera. “Your work is easier when you consider the reinforcements from the beginning. The lead model of the Nine-Nine-Seven series was the convertible.” In the past, Porsche had developed coupes first and when engineers had completed that, they started on open cars. With the 997, Achleitner’s team developed both simultaneously. The 997 largely was his creation; before that time, from 1989 through 2000, he had directed new vehicle concepts and packaging for all Porsche vehicles.
Starting with the cabrios provided Weissach’s engineers some unexpected benefits as they worked through target conflicts. These were the good news/bad news dilemmas arising when one decision revealed two or three more choices. Wolfgang Dürheimer, Porsche’s vice president for research and development, explained the advantages the 997 derived from Achleitner’s simultaneous effort.
Loyalists and longtime customers welcomed back Porsche’s traditional round-oval headlamps. Fenders rose more prominently than they had with the 996.
The 911 heritage offered as many challenges to engineers and designers as it provided guidelines. Its characteristic front fenders retained a form that, as Ferry Porsche first dictated to Erwin Komenda for the 356, allowed the driver to see where the front wheels were located. The 911 carried on the iconic angled-down roofline that F. A. Porsche and his clay modelers had created. It still defined itself with the rear engine that dictated the car’s shape, its handling, its sound, and its appeal.
Engineers boasted that the new 997 was 80 percent changed from the 996. More than half of that was beneath the surface. Not a single suspension piece was interchangeable. This situation flew in the face of Wendelin Wiedeking’s often repeated goal of commonality of parts. But many of the new pieces were simpler to manufacture and easier to install. The 20 percent that remained unchanged included expensive elements such as the roof panel, the interior rear seats, and the 3.6-liter engine block, crankshaft, and pistons.
Nineteen-inch wheels forced powertrain engineers to rework gearboxes. Larger rolling circumferences required shorter final drive gears to take best advantage of engine torque and horsepower. Weissach engineers reexamined the manual and Tiptronic transmissions. They developed a new six-speed manual gearbox with torque and horsepower capacity to spare. Engineers increased gearshift pressure and stall speed on the five-speed Tiptronic. This gave drivers faster starts from a standstill, more powerful and spontaneous acceleration, and quicker shifts, especially in lower gears.
Engineers gave the 997 an automatic stability system known as Porsche Active Suspension Management (PASM).
Other than the 959, which many in the company considered to be a large run of prototypes, this 997 was the first time Porsche offered an electronic spring and damper system. In the cabrio, this was an industry first. Engineers substituted the coupe’s front springs with coils 10 percent softer for the cabrio and substituted the coupe’s rear suspension bushings with some much harder for the open car. They compressed PASM’s range of variability to fit the cabriolet’s slightly diminished stiffness and the anticipated character of its drivers. Its stiffest “sport” settings were roughly 15 percent softer than calibrations for the coupe, while the softest point was slightly gentler than the coupe’s.
The company sold coupes alone for the first few months. The base Carrera 3,596cc (219.4-cubic-inch) M96/05 engine developed 325 horsepower at 6,800 rpm. The S M97/01 engine displaced 3,824cc (233.3 cubic inches) and produced 355 horsepower at 6,600 rpm.
For 997 coupes, Porsche offered a full “Sport Suspension” for European customers. This lowered ride height by 20mm (0.79 inches), setting it too low to meet U.S. federal ride height standards. Engineers provided a mechanical differential lock on the rear axle of 22 percent under acceleration and 27 percent under deceleration or braking to enhance directional stability. Buyers could order it through Porsche Exclusiv as an option on the Carrera or in place of the PASM on the Carrera S. The ride was much harsher because Porsche conceived it “for the ambitious driver not so much interested in comfort but rather in super performance and agility,” Achleitner explained.
Power train manager Stefan Knirsch and his staff devised intake and exhaust modifications to the familiar 3,598cc 996 engine that added 5 horsepower to reach 325 SAE horsepower for the base Carrera. This engine carried over the VarioCam Plus valve management system comprising two interacting switching cup tappets on the intake side of the engine, driven by two cams of varying size on the intake camshaft.
Enlarging cylinder bore from 96mm to 99 but retaining stroke at 82.8mm brought a new S engine displacement to 3,823cc or 3.8 liters (233.2 cubic inches). The car developed 355 SAE horsepower. Coupes reached 60 miles per hour in 4.8 seconds (5.2 for the cabriolet) and in 4.6 seconds for the S (but 4.9 seconds for the S cabriolet). Porsche quoted top speeds of 177 miles (283 kilometers) per hour and 182 miles (291 kilometers) per hour, respectively. This was the first time since 1977, with 2.7-liter and 3.0-liter engines, that Porsche offered two normally aspirated engines simultaneously.
Porsche introduced the 997 in mid-2004 as a 2005 model. It offered two versions, the Carrera, with an update of the 3.6-liter engine from the 996, and the Carrera S, with a new 3.8-liter flat six.
Porsche introduced the 997 Carrera and Carrera S coupes in summer 2004 as a 2005 model in Europe and the United States. Through the model year, it continued manufacturing and selling 996 Turbo S and Turbo S cabriolets (installing the X50 option as standard equipment, providing the cars with 444 SAE horsepower). Cabriolet versions of the 997 Carrera and Carrera S reached dealers worldwide in April 2005. The first all-wheel-drive models arrived in showrooms in midsummer, with Targases, Turbos, GT3s, GT2s, and other models following into 2006, 2007, and 2008.
The 997 interior was nearly all new, except for the rear seats and a few details. It was the work of interior designer Anke Wilhelm and interior chief Franz-Josef Siegert. In the late 1990s, Harm Lagaay had hired Siegert away from Mercedes-Benz, and Siegert brought in a staff of designers only to do interiors and still others to attend to the details, the jewelers, as he called them. Wilhelm and Siegert’s instrument pod seemed familiar to Porsche owners, and Uli Sauter’s graphics were quickly comprehensible to those driving a Porsche for the first time. The 996 interior was the most comfortable and user friendly of any previous model. Porsche would not shy away from its new enthusiast base. The 997 offered four seat options to satisfy most backs and body shapes.
All were comfortable and supportive, with headrests 50mm (2 inches) higher and angled closer for better support. There was more metal and less plastic in this new interior than ever before.
Forty percent of all 997s for 2005 were cabriolets, and about 50 percent of those went to the United States. The solid fixed-glass back window with an electric defogger was one of many selling points, introduced at the 996 face-lift in 2002 and slightly enlarged with the 997. At speeds up to 30 miles (50 kilometers) per hour, the 997 driver could raise or lower the roof. That process, including dropping and raising side windows, took 20 seconds in either direction.
The new steering wheel controlled functions ranging from the navigation system, and radio tuning, to telephone functions. New seats offered optional electric side-bolster adjustment.
Porsche’s wholly owned subsidiary Car Top Systems (CTS) developed the mechanism for the 997’s top and manufactured the complete system, with bows, hinges, motors, inner lining, glass, and outer material. The system arrived from CTS fully assembled and, like everything else on the Zuffenhausen assembly line, just in time for two men to lift it and set it onto a painted car body. The entire assembly weighed 93 pounds (42 kilograms). But weight is always an enemy to Porsche engineers. While the cabriolet gained a total of 297 pounds (135 kilograms) over the coupe, diligent management of every system kept the net weight increase to 187 pounds (85 kilograms).
Because the roofline could not exactly mimic the coupe’s, engineers tweaked rear spoiler performance. It rose 20 millimeters (0.80 inches) higher on the cabriolet than on the coupe to provide more aerodynamic effect. The subtly higher wing was not the only effect that top-down Porsche drivers noticed. “The exhaust sound was even more aggressive with the cabrio,” Bernd Kahnau explained with a broad grin. “Because of the open cabin, we wanted our customers to really be able to hear the engine.” It reminded some drivers of the 993 more than a water-cooled 996. Because of America’s relaxed exhaust noise standards, U.S. buyers got the loudest exhausts of any 997 purchasers. Bernd Kahnau knew the sound and explained the reason: “Our exhaust engineers? They are our Mozarts.”
For 60 years, Porsche had listened to its engineers and designers as they continued to deliver Ferry Porsche’s dream car to an ever-changing world. Dr. Erhard Mössle, the four-wheel-drive manager for the 997 Turbo, gave an example.
His team had identified “characteristics of the Targa buyer,” he explained. “They desire exclusivity, distinctive design. They primarily are cruisers, you know, connoisseurs of automobiles rather than racers. And traditionally, they are safety conscious.” So Porsche “repositioned” the Targa to differentiate it from those that came before and from the cabriolet and coupe.
For Mössle, whose title is product manager four wheel drive, and for his team, the decision to start with the C4 and C4S platforms immediately addressed and resolved questions about what the new Targa would be. The 44mm (1.7 inch) wider rear end provided the aggressive and dynamic form that engineers and stylist Mathias Kulla had in mind. This single decision gave them the distinctive appearance, as well as safety and stability controls, they believed appealed to potential Targa buyers. Porsche’s engineers and marketers understood that these owners routinely used their cars year-round in climates with snow, so the C4 drive system made further sense. Its 10mm (0.4 inch) lower ride height didn’t hurt its overall visual appeal either. But each of these factors combined to preclude any possibility of a Targa 2 or Targa 2S.
“The glass roof,” Tomas Christiansen, manager of body engineering, explained, “is lighter than the glass in the 996. This makes a very big difference so high above the center of gravity. It is two kilograms [4.4 lbs] less, even with the hatchback mechanism.”
The C4S, in its own right and as the basis for the Targa, was so thoroughly tamed beyond even its 996 predecessor that heavy front-end sensations that engineers anticipated never appeared. Porsche derived and developed the C4 964, introduced in 1989, with the U.S. market in mind. It tended to understeer when drivers pushed it too hard. This was a comfortable response for most Americans, and Porsche engineers—dealing also with a heavy load of equipment up front—settled for this reaction. In the 993 they compensated; some say they overcompensated. This car produced handling characteristics that were more rear dominant, reminiscent of earlier two-wheel-drive 911s. With the 996 and 997 C4 and C4S, turn-in was crisp, precise, predictable, and dependable.
Porsche began shipping its all-wheel-drive 997 C4 and C4S models to the United States in November 2005. The Turbo followed, shown first at Geneva in February 2006 along with the GT3, the other model guaranteed to quicken the purist’s pulse. The 3.6-liter Mezger engine developed 480 SAE horsepower in the Turbo. Acceleration to 62 miles per hour took 3.9 seconds, and Porsche quoted its top speed as 193 miles (311 kilometers) per hour. In a testimony to Weissach’s engineering, the Tiptronic version of the all-wheel-drive Turbo was even quicker, reaching 62 miles per hour in just 3.7 seconds. The Turbo cabriolet arrived in September 2007 boasting nearly identical performance figures, a longtime goal for Weissach’s engineers. Marketing’s tendencies for greater luxury in its flagship Turbo models continued with the latest generation. Fully optioned Turbos elevated high performance to performance art, especially if buyers optioned “paint to match” exterior color schemes and interior leather and other appointments from Porsche Exclusiv.
Porsche introduced the 997 Cabriolet models in early April 2005. As with the coupes, the new open cars were available as Carrera and more potent Carrera S models.
The base Carrera developed 325 horsepower. The cabriolet weighed 1,480 kilograms, 3,256 pounds. With the 997 model, Porsche made the removable hardtop an extra-cost option.
Engineers and designers worked to improve the operation and appearance of the collapsible fabric top when it was up. Their goal was to come closer to the shape of the coupe.
The Sport Chrono Plus feature, identified by the analog/digital stopwatch installed in the dashboard, added significant performance potential to the Carrera S models. Sports Chrono allowed drivers to switch engine management programs to improve driving enjoyment over repeated roads.
To honor Porsche’s long relationship with PCA, the Porsche Club of America, Weissach designers, engineers, and planners created a “Club” coupe painted in the PCA logo blue for the 2006 model year.
The Carrera S rode on 235/35ZR19 front tires and 295/30ZR19s on the rear. The coupe weighed 1,420 kilograms (3,124 pounds). Sport Suspension lowered ride height by 20mm (0.8 inches).
Carrera S coupes accelerated from 0 to 100 kilometers per hour in 4.8 seconds. Porsche quoted a top speed of 293 kilometers (182 miles) per hour.
YEAR
2005-2008
DESIGNATION
911 Carrera
SPECIFICATIONS
MODEL AVAILABILITY
Coupe, Cabriolet
WHEELBASE
2350mm/92.5 inches
LENGTH
4427mm/174.3 inches
WIDTH
1808mm/71.2 inches
HEIGHT
1310mm/51.6 inches
WEIGHT
1395kg/3069 pounds
BASE PRICE
$69,300 coupe - $79,100 cabriolet
TRACK FRONT
1486mm/58.5 inches
TRACK REAR
1534mm/60.4 inches
WHEELS FRONT
8.0Jx18
WHEELS REAR
10.0Jx18
TIRES FRONT
235/40ZR18
TIRES REAR
265/40ZR18
CONSTRUCTION
Monocoque steel
SUSPENSION FRONT
Independent, wishbones, semi-trailing arms, MacPherson struts w/coil springs, gas-filled double-tube shock absorbers, anti roll bar
SUSPENSION REAR
Independent, multi-wishbone, progressive coil springs, gas-filled single-tube shock absorbers, anti roll bar
BRAKES
Ventilated, drilled discs, 4-pisto
n aluminum monobloc calipers
ENGINE TYPE
Horizontally opposed water-cooled DOHC six-cylinder Typ M96/05
ENGINE DISPLACEMENT
3596cc/220.0CID
BORE AND STROKE
96x82.8mm/3.78x3.26 inches
HORSEPOWER
325@6800rpm
TORQUE
273lb-ft@4250rpm
COMPRESSION
11.3:1
FUEL DELIVERY
Bosch DME with sequential injection
FINAL DRIVE AXLE RATIO
3.44:1
TOP SPEED
178mph
PRODUCTION
coupe: 6,239; cabriolet 3,019
2006-2008 GT3
The GT3 appeared alongside the Turbo in Geneva in 2006. This normally aspirated version of the Mezger 3.6-liter flat six achieved 415 SAE horsepower in this incarnation, giving owners acceleration to 60 miles per hour in 4.1 seconds and a top speed of 193 miles (311 kilometers) per hour. Project leader Andreas Preuninger explained the genesis and evolution of the car, still a homologation “special”: “It’s as close as you can get to a race car with a license plate on it. We wanted to translate the feeling a race car gives you, the emotion, the wish to drive to your destination in a circle, not in a straight line, because you don’t want to get out of the car!”