Next Generation Porsche 911 Cabriolet - In Detail

Press Release

New design includes lightweight top, more powerful engines and advanced technologies

Just months after launching the highly acclaimed new Porsche 911 Carrera and 911 Carrera S Coupes, Porsche introduces the Cabriolet versions of both cars as 2005 models.

The Coupes may have been the first new 911 s to reach Porsche dealer showrooms, but the hard and soft-top versions were designed and developed in parallel from the very beginning. Right from the start, the car's structure was designed to provide the stiffness and strength necessary for outstanding dynamic performance and exceptional safety protection, regardless of the material comprising its roof.

Porsche enhances the cabriolet experience

Thus the 2005 Porsche 911 Carrera and 911 Carrera S Cabriolets not only match the coupes in their top speed potential, but have safety features that provide:

• unparalleled low weight among cabriolet roof structures;
• a lower center of gravity - and thus better vehicle dynamic control - than even other sports car cabriolets;
• opening or closing of the top while the car is moving at speeds of up to 31 miles per hour (50 km/h);
• a standard wind deflector to assure as calm and quiet a passenger compartment whether the top is up or down;
• six airbags, including head-protecting airbags that emerge from the top of the doorsills, as standard equipment;
• supplemental safety bars behind each seat that automatically extend when sensors detect a potential rollover situation;
• Porsche Stability Management, a technology to help the driver maintain control in emergency situations, as standard equipment.

Just like the 911 Coupes, the 2005 Porsche 911 Carrera S and 911 Carrera S Cabriolets also come with more powerful engines, the latest update of the both chassis and the classic 911 silhouette and body, as well as all-new interiors and the availability of such advanced technological innovations as Porsche Active Suspension Management, Porsche Ceramic Composite Brakes and the Porsche Sports Chrono Package Plus.

Cabriolets are just as fast as Coupes

The introduction of the 2005 Porsche 911 Carrera and the 2005 Porsche 911 Carrera S marked the first time since 1977 that Porsche equips the 911 with a range of engines, and those same engines power the new Cabriolets. The 2005 Porsche 911 Carrera Cabriolet is propelled by a 3.6-liter flat six-cylinder engine with 325 horsepower (SAE) while the 2005 Porsche 911 Carrera S Cabriolet draws on a 3.8-liter flat six that provides 355 horsepower (SAE) and 295 pound-feet (400 Newtonmeters) of torque.

With those engines and their advanced aerodynamics, including a rear spoiler that extends 0.79 inches (20 mm) more than the spoiler on the coupes, the convertibles are capable of achieving the same top speeds as the hard-topped versions - 177 miles per hour (285 km/h) for the 911 Carrera Cabriolet and 182 mph (293 km/h) for the 911 Carrera S Cabriolet.

The 2005 Porsche 911 Carrera Cabriolet sprints from a standing start to 60 miles per hour (96 km/h) in just 5.0 seconds and continues on to reach 100 mph (160 km/h) in a mere 11.4 seconds. The 2005 Porsche 911 Carrera S Cabriolet is even faster.

S designates special Porsche models

An "S" designation has a very special meaning at Porsche, signifying a unique model, not a mere trim upgrade or option package.

The first Porsche to wear an "S" badge was the 1952 356 equipped with the 1.5-liter "Super" engine. Perhaps the most famous "S" model in the company's history was the 911 S launched in 1967, though modern Porsche enthusiasts might tell you their favorite is the Carrera 4S. In recent years, Porsche has offered higher-performance models of the Boxster® roadster and Cayenne® sport utility vehicle designated as the Boxster S and Cayenne S.

The larger and more powerful new 3.8-liter engine is only one of several features that distinguish the 2005 Porsche 911 Carrera S Cabriolet, which also comes with the new Porsche Active Suspension Management technology, larger brakes with red-painted calipers, larger wheels, standard Bi-Xenon headlights, a sports steering wheel, aluminum-look interior trim and a silver-colored rear deck lid logo.

With this new powerplant, the 2005 Porsche 911 Carrera S Cabriolet can accelerate from a standing start to 60 miles per hour (96 km/h) in just 4.7 seconds. It can reach 99 mph (160 km/h) in a mere 11.0 seconds.

Lower center of gravity

Contributing to the dynamic capabilities of both the 2005 Porsche 911 Carrera Cabriolet and 2005 Porsche 911 Carrera S Cabriolet is a carefully designed convertible top. While fully suited for even the coldest winter weather, the new top weighs only 93 pounds (42 kilograms) - including all of its system components. This represents only half of the weight of a collapsible metal roof like those used on some premium-class convertibles.

This lighter weight top and system components also help to lower the center of gravity of the new Porsche convertibles, thus enhancing the cars' dynamic potential.

Also contributing to this new lower center of gravity is the re-engineered 2005 Porsche 911 chassis that features a lower seating position.

By designing Coupe and Cabriolet in parallel, Porsche engineers were able to place necessary structural components in the convertible right from the start. As a result, the new cabriolet body-inwhite is five percent more resistant to torsional bending and nine percent stiffer in regards to static flexing, yet weighs only 15.4 pounds (seven kilograms) more than the coupe body.

Even with the motors needed to operate its Z-folding top, the 2005 Porsche 911 Carrera and Carrera S Cabriolets weigh only about 180 lbs. (85 kg.) more than their Coupe counterparts.

The all-weather Cabriolet

The 2005 Porsche 911 Carrera Cabriolet and 2005 Porsche 911 Carrera S Cabriolet optimize the driving experience whether the top is up or down, rain or shine.

In inclement weather, new water ducts above the doors prevent rainwater from dripping down. Instead, the water flows into a door-seal drain in the A pillar (next to the windshield). The top also features a glass rear window with an integrated defroster.

In top-down weather, the standard wind deflector helps to keep the cockpit calm enough for conversation between driver and passenger, even at considerable rates of speed.

Should the weather change suddenly, the top can be opened or closed, in a mere 20 seconds. It can also be opened or closed in 26 seconds while the car is moving at up to 50 kilometers per hour (31 mph). The top is designed in a "Z" configuration so that when it folds, it's outer side faces up and also helps to protect the glass window.

Designed for safety

The new Porsche Cabriolets also were designed for safe motoring.

In addition to an extra-stiff new body shell designed to provide maximized energy absorption in a collision, the cabriolets have supplemental safety bars with elements made of ultra-strong steel as well as six airbags, all as standard equipment.

The airbags include those in front of the driver and front-seat passenger, as well as side (thorax) airbags mounted in the outside front seat backs and head-protecting airbags mounted in the top of the interior door panels. Together, these airbags and front seat and shoulder belts with belt-latch tensioners and belt-force limiters form (POSIP), the Porsche Side Impact Protection system.

In addition, a new rollover sensor integrated into the airbag control unit positioned in the middle of the car deploys the supplemental safety bars and activates the seat-belt tensioners when it recognizes the dynamic forces that could lead to a rollover situation.

Porsche Stability Management provides active safety

To further enhance dynamic control, all 2005 Porsche 911 Carrera Cabriolets and 2005 Porsche 911 Carrera S Cabriolets are equipped with the new, second-generation Porsche Stability Management (PSM®) as standard equipment. PSM is a technology designed to help the driver maintain control of the car.

Porsche Stability Management uses data from several sensors to detect a loss of grip and enhances driver control by applying braking to individual wheels and, if necessary, by reducing engine torque. For 2005, PSM benefits from new anti-lock brake sensors that take their readings not from conventional wheel pulses but from multi-pole seats fitted directly on the wheel bearings. These improved signals allow more precise processing and control. Instead of conventional shaft valves, linear solenoid valves adjust brake pressure with nearly infinite precision.

To provide pressure more quickly, a new hydraulic pump is used, while a pre-charging pump and its connections are eliminated, reducing system weight by 25 percent, or 6.6 pounds (three kg). Another enhancement to PSM for 2005 gives the enthusiast driver more control over the system. In the past, PSM could be turned off by a switch on the dashboard. And automatically reactivated when the brake pedal was depressed. For 2005 the system reactivates only when the pedal is pushed hard enough to exceed the ABS control threshold on at least one front wheel. This change allows the enthusiast driver more dynamic freedom, including slight use of the brakes in curves.

Aerodynamically efficient

Sharing most of its body components with the Coupes, the new Porsche Cabriolets have a low drag coefficient of 0.29. With special airflow engineering over, under and around the car, including the rear wing with its extra reach, the lift forces on the front and rear axles of the new Porsche Cabriolets remain consistently close to zero all the way to the car's top speed range.

Wider track

With a wider track and slimmer, more accentuated waistline, the 2005 Porsche 911 Carrera Cabriolet and Porsche 911 Carrera S Cabriolet have a more powerful and athletic stance, and those characteristics are more than cosmetic changes; the car has an expanded envelope of dynamic capabilities.

While the wheelbase remains 92.5 inches (2,350 mm) and overall length and height are increased by less than two-tenths of an inch compared to the previous 911, the 2005 models ride on front and rear tracks that are nearly an inch wider than previously. Overall width is nearly 71.2 inches (1,808 mm), almost an inch and half wider than the previous generation.

Wider, lighter suspension

Front and rear, the suspension has been re-engineered to enhance ride and handling characteristics. With performance and safety in mind, Porsche engineers redeveloped the front axle sub frame, widening the structure and the axle pivot points by 1.18 inches (30 mm). To reduce weight and to improve airflow to the brakes, new hollow front axle pivot bearings replace solid components and reinforced and larger diameter wheel mounts are used. To enhance ride comfort, hydraulic suspension mounts are used, suppressing high-frequency vibration and minimizing the transmission of unwanted vibrations to the steering system.

In the rear, the axle is 1.34 inches (34 mm) wider and the multi-arm axle and its aluminum sub frame are made of more rigid components. However, the sub frame also is lighter, by approximately 2.2 pounds (one kg). Porsche engineers moved the pivot points of the upper track control arms up by 0.39 inches (10 mm) and the pivot points of the lower arms down by 0.20 inches (five mm), increasing the anti-squat effect by 25 percent, providing better support of lateral forces and assuring directional precision in turns.

A new hollow-cast aluminum wheel mount that is 10 percent lighter but also stiffer than the former solid component.

Anti-roll bar pivot points have been changed to provide more direct response, reduce body roll in turns and reduce friction, which enhances the sensitivity of new aluminum springs that are some 70 percent lighter than conventional steel springs.

Instead of steel and rubber, rear suspension mounts use internal elastic foam that reduces weight by 45 percent and improves noise and vibration control.

A new generation of tires designed to convey higher forces in both longitudinal and lateral acceleration enhance the performance of the suspension system. The 2005 Porsche convertibles wear a new generation of tires designed to convey higher forces in both longitudinal and lateral acceleration. The 2005 Porsche 911 Carrera Cabriolet rides on 18-inch wheels that are 8 inches wide in front and 10 inches wide in the rear. The 2005 Porsche 911 Carrera S Cabriolet has 19-inch wheels, also 8 inches wide in front but 11 inches wide at the rear.

Porsche Active Suspension Management

Standard on the 2005 Porsche Carrera S Cabriolet and optional on the 2005 Porsche Carrera Cabriolet is the new Porsche Active Suspension Management System (PASM), which uses active damping technology to provide two suspension systems in one – one designed for an athletic yet comfortable ride, the other for performance driving situations.

By pressing a button on the center console, the driver can switch from PASM “Normal� to PASM “Sport.� Even in normal mode, the PASM suspension lowers the car by 0.39 inches (10 mm) compared to the standard 911 Carrera suspension setup. When switched into its sport setting, PASM activates a firmer damper control map to provide extreme agility and dynamic control that minimizes body roll.

There are advantages to PASM even when left in its normal setting because it automatically adjusts to changes in driving style, gradually becoming firmer to respond to greater dynamic forces.

The PASM system combines continuously adjustable shock absorbers, a pair of accelerometers – one in the front right damper dome, the other in the left rear – that determine vertical movements of the car’s body and an electronic control unit that also has access to steering angle, road speed, brake pressure and engine torque figures and thus can provide optimum damper control for each wheel through the active dampers that have a similar structure as standard shocks, providing damping with oil pressure, but that also have a bypass valve that opens and closes to increase or reduce the oil flow as needed. (Should the system fail, the bypass valve automatically closes, putting PASM into its hardest position to assure the safety dynamic driving mode.)

Settings for any driving situation

PASM is equipped with five special software modules – lane change, vertical control, lateral acceleration, brake and load change – to provide optimum settings for any driving condition: Lane change module: In response to rapid movements of the steering wheel in a sudden maneuver, the system instantaneously increases damper forces on both axles, reducing any tendency toward sway or rocking.

Vertical control module: In the normal program, damper forces increase whenever vertical movement of the car’s body exceed a threshold, for example, when driving on a bumpy surface. This prevents any risk of the body starting to rock. However, when in the sport program, the system reduces the damping effect to maintain wheel contact with a rough surface, preventing the risk of the car “jumping� around. Lateral acceleration module: In the normal program, damping varies through a curve, adjust with road speed and lateral acceleration.

Brake module: As soon as the driver applies the brakes, PASM firms damping to reduce body dive, ensuring faster transmission of brake forces to the road. Then, at a certain point in the braking process, the system switches to softer damping, with different forces applied in the front and rear of the car. This ensures better surface contact and shortens stopping distances, even on rough roads.

Load change module: In all-out acceleration, with the driver lifting off the accelerator while shifting gears, the control maps are adjusted for the front and rear axles. In the normal mode, harder damping is used briefly to prevent too much squat. In the sports mode, a softer damper response is used to improve traction, for example, on a rough road surface.

No spare tire

Because of improved tire technology, and to reduce the weight of a spare, jack and tools (some 22 pounds or 10 kg.), the 2005 Porsche 911 Carrera Cabriolet and 2005 Porsche 911 Carrera S Cabriolet dispense with those accessories and replace them with tire sealant and an electrical air compressor, allowing emergency repair of a small puncture and the ability to drive at speeds of up to 50 mph (80 km/h) without damaging the wheel.

Optional for the first time on both cabriolets is a tire pressure control (TPC) system that monitors the pressure within each tire as well as tire temperatures and warns the driver through a signal on the instrument cluster if there is inadequate pressure or a gradual or sudden lost of pressure.

Reinforced brakes on Carrera S

The 2005 Porsche 911 Carrera Cabriolet and the 2005 Porsche 911 Carrera S Cabriolet stop with the sort of braking authority that characterizes the dynamics of all Porsche vehicles. The 911 Carrera Cabriolet has 12.53-inch (318 m) front rotors and 11.77-inch (299 mm) rear rotors, all cross-drilled and inner-vented with black-colored, monoblock, four-piston calipers. Compared to the former model, the brake servo has been increased by 17 percent to 4.5:1, reducing the force needed on the pedal and providing more spontaneous braking response. Braking cooling also improves for 2005, thanks to the new front axle pivot mounts and enhanced under-vehicle airflow.

The 2005 Porsche 911 Carrera S Cabriolet has even larger brakes: reinforced four-piston monoblock red-painted fixed calipers front and rear with 12.99-inch (330 mm) front and rear discs and larger brake pads.

Porsche Ceramic Composite Brakes

Porsche Ceramic Composite Brakes are available on the Cabriolets. Instead of metal, the 13.78-inch (350 mm) brake discs are a ceramic material that provides high and consistent levels of friction during application. They also weight approximately 50 percent less than metal discs and thus reduce unsprung masses, by 34.4 pounds (15.6 kg).

For 2005, the Porsche Ceramic Composite Brakes are more rigid, yet include more interior cooling ducts. Fiber reinforcement on the friction surface is increased, significantly enhancing resistance to abrasion under high loads.

New variable-ratio steering

For the first time, the 911 Cabriolet now comes with standard variable-ratio steering that enhances the car’s agility on winding roads while retaining exceptional stability at higher speeds. When the steering wheel is turned with 30 degrees of its centered position, the steering ratio remains similar to that on the previous generation 911. This assures a smooth and calm driving experience, even on rough surfaces on which a driver might have a tendency to steer too much.

However, when the steering wheel angle exceeds 15 degrees from center in either direction, the steering ratio becomes more direct, reducing the lock-to-lock ratio from its usual 2.98 to only 2.62. This gives the driver better control both on fast, winding roads and in slow-speed parking maneuvers.

In addition to the new variable ratio technology, the Cabriolets have steering columns that both tilt and telescope to better fit each driver. The wheel can be adjusted by 1.57 inches (40 mm) both in height and reach. The steering system also includes a new electric steering wheel lock integrated into the car’s anti-theft immobilizer system.

Improved aerodynamics

The Cabriolets’ design evolution features a new, oval-shaped headlamp set into an arching front fender with separate turn indicator and fog lamps set horizontally into the curving edges of the front bumper above redesigned air inlets.

Smoothing the surfaces and enhancing the design of transitional areas beneath the front of the cars to create a low-pressure area that increases downforces on the front axle also help grip. The section radii of the front end and wheel wells also controls airflow to reduce lift. Special air ducts on the vehicle’s new, longer and smoother under-floor cover helps to direct cooling flow to the brake discs, transmission and differential. The cover itself significantly reduces air resistance and lift.

Wheel spoilers are used to reduce drag by guiding air around the wheels. Optimized brake air spoilers and pivot bearings ensure effective air around the discs, reducing brake disc temperatures by some 10 percent.

The new design also includes new double-arm rearview mirrors. The mirrors, similar in design to those on the Porsche Carrera GT supercar, guide air along the side of the car toward the rear spoiler, thus reducing turbulence that might otherwise result in wind noise inside the vehicle’s cabin. At the same time, the design of the mirrors helps to keep dirt and moisture off the side windows. The mirror casing and double-arm design increases downforce on the front axle and, by channeling air toward the rear spoiler, increases positive forces on the rear axle as well.

The flow of air used to provide engine cooling improves by some 20 percent. Air leaving the front radiator flows sideways into the wheel arch rather than downward in front of the wheels. This reduces losses in the airflow ducts and minimizes lift effects on the front axle.

Special ram-air flaps around the engine fan also boost cooling airflow without having to enlarge the air scoop openings. At low speeds, the flaps remain closed and air is drawn only through the heat exchanger, but at around 45 mph (70 km./h), the flaps open under ram pressure and provide enhanced cooling.

Taut, tones styling cues

From a side view, fenders are more muscular and wheel arches are more accentuated and doors are inset with more pronounced lower sills. Improved sealing allows a slimmer cross-section for windshield, side and rear window elements and enhances the overall appearance of the greenhouse detailing.

The rear view of the car features flared wheel wells and wide, brilliantly lit, red and silver tail lamps on either side of the engine cover. Distinctive air scoops built into the rear spoiler and higher mounting of the third brake light emphasize the enhanced power of the rear-mounted boxer engines.

Tail pipes are distinctive

To distinguish the 2005 911 Carrera Cabriolet and the 2005 911 Carrera S Cabriolet from behind, the S model has twin round tailpipes on either side while the Carrera has a pair of oval-shaped exhaust pipes.

The tail pipes are part of an all-new exhaust and catalyst system designed to make the convertibles even cleaner in their exhaust emissions. The Carrera S Cabriolet is equipped with an exhaust manifold with much shorter individual pipes designed to lower cold-start emissions from the more powerful engine. Both cars use the same two-stage “cascade� style catalyst designed to reach operating temperature more quickly and efficiently.

The new exhaust system makes the cars some 15 percent cleaner than on previous models.

More powerful 3.6-liter engine

While the 3.6-liter engine in the 2005 Porsche 911 Carrera Cabriolet is familiar, fine-tuning, especially of the air filter, has increased output by five horsepower. Torque remains at 273 pound-feet (370 Newton meters) at 4,250 rpm.

Crucial to the engine’s performance is Porsche’s patented VarioCam® Plus valve management technology that combines camshaft control on the intake side with variable valve lift. VarioCam Plus adjusts camshaft position to provide continuously adjustable valve timing and also incorporates two camshaft profiles and two sets of tappets to vary valve lift and duration. This system helps to both “fatten� and smooth the torque curve while reducing emissions. To provide optimum oil flow through the alloy engine block and cylinder heads, Porsche uses integrated dry sump lubrication and three oil pumps – one in the crankcase and additional pumps within each cylinder head, thus assuring proper lubrication despite the forces of hard acceleration, braking or cornering.

For 2005, the oil pump on the 4-5-6 cylinder head is combined with a pneumatic vane-cell pump to provide necessary vacuum for the brake servo as well as the engine and transmission control systems. This technology greatly reduces hydrocarbon emissions following a cold start and engine warm-up.

3.8-liter engine for Carrera S

To create the more powerful 3.8-liter engine that provides 355 horsepower for the 2005 Porsche 911 Carrera S Cabriolet, engineers did more than simply increase the bore diameter by 0.12 inches (three mm). They also changed the intake manifold and modified the intake camshaft lift pattern. Injector angles have been changed, assuring that more fuel goes to the center of the combustion chamber in the intake stroke. This means an even better fuel/air mixture, reduces exhaust emissions (even after a cold start) and produces more torque than the 3.6-liter throughout the power curve.

The entire intake system was redesigned and provides smoother flow with less resistance.

A Helmholtz resonator is used to refine acoustics. This provides more than 18 cubic inches (0.3 liters) of additional resonance volume between the hot-film air mass meter and the throttle butterfly and is activated between 5,000 and 6,000 rpm to reduce oscillations in intake sounds. Porsche has applied for a patent for this technology that provides a deep, throaty sound without aggressive peaks.

Higher combustion forces produce more power but also more torsional crankshaft vibration, so Porsche engineers have integrated a vibration damper in the pulley at the end of the crankshaft. Conventional vibration dampers are made of cast iron but Porsche engineers devised an aluminum damper that reduces weight by some 3.3 pounds (1.5 kg) while controlling vibrations to a level even lower than the 3.6-liter engine.

Amazingly, the 3.8-liter engine weighs no more than the 3.6-liter unit thanks to its lighter intake manifold and weight optimization within the cylinder head.

While the 3.8-liter engine uses twin radiators like the 3.6-liter powerplant, it has a higher performingcooling pump and an oil/water heat exchanger with two additional cooling layers.

New six-speed manual transmission

To deal with the new engine’s 295 pound-feet of torque, Porsche developed a new six-speed manual gearbox that is used on both the 2005 Porsche 911 Carrera Cabriolet and the 2005 Porsche 911 Carrera S Cabriolet.

The transmission has thicker shafts and wider gears but weighs no more than the previous manual. Extra-thin aluminum used for oil chamber walls save weight and also reduce splash effect and flow losses and thus increase the efficiency of the gearbox.

Even though gear ratios have been reduced by around five percent, the use of larger rear wheels results in achieving top speed in sixth gear just before maximum engine speed is achieved.

While brass synchronizing rings were formerly used, the new transmission has steel rings in all gears and thus can handle higher power loads. For the first time, Porsche uses wear-resistant carboncoated first, second and third-gear synchronizing rings, and boosts from double to triple synchronizing for first and second gears and from single to double for third gear, retaining single synchronizing for gears four, five and six.

The driver will notice this change in the reduced forces and shorter travel needed to change gears. Shifter travel is reduced by some 15 percent. Shifting also is smoother and more precise because of relocation of the shift lever pivot point and lower-friction shift cables.

Porsche’s single-disc dry clutch with lead-free pads is retained for the 2005 Porsche 911 Carrera Cabriolet while the 2005 Porsche 911 Carrera S Cabriolet gets a new self-adjusting clutch.

Enhanced Tiptronic S available

Tiptronic S is Porsche’s optional automatic transmission system that allows manual gear selection via switches on the steering wheel. The five-speed unit allows the driver to use the thumb switches to change gear momentarily, for example, for passing or to downshift for a curve, even while the floor lever remains in its automatic position.

Several modifications have been made to Tiptronic S in conjunction with the increased torque produced by the 3.8-liter engine in the 2005 Porsche 911 Carrera S Cabriolet.

Now, instead of making the first-second shift at 6,900 rpm under full power acceleration, Tiptronic S holds first gear until the engine achieves 7,200 rpm.

In addition, the oil pressure build-up has been fine-tuned and clutch plates modified to allow the Tiptronic S to shift more smoothly.

Throttle tip-in mimics enthusiast’s driving technique

To mimic the way an enthusiast driver manipulates the accelerator, brake and clutch, changes to the engine management software now produce a slight boost in engine speed during aggressive downshifting, such as that done while applying the brakes. This shortens shift time and enhances gearshift mesh.

The PSM OFF function also has been modified so that when the Tiptronic S selector lever is in its manual mode and the PSM OFF switch is activated, the transmission will not shift up even when the engine reaches its rev limit. This allows the enthusiast driver to drive with the engine near its rev limit while maintaining the selected gear.

As with the six-speed manual transmission, a shorter spur gear ratio works in conjunction with the larger standard rear wheels to achieve maximum top speed in the top (fifth) gear.

To keep the enhanced Tiptronic S operating at proper temperatures, the gearbox is equipped with an additional oil/water heat exchanger with two additional cooling layers and with a more powerful coolant pump.

Redesigned interior

The interiors of the 2005 Porsche 911 Carrera Cabriolet and 2005 Porsche 911 Carrera S Cabriolet have been completely redesigned with new steering wheels, seats, gauge cluster, improved climate control, standard Porsche Communication Management (with available DVD navigation system), updated audio, upgraded anti-theft system, six standard airbags and the new Sport Chrono Package Plus option.

New steering wheel design

The steering wheels have a new and more dynamic three-spoke design and are adjustable both in height and reach. In keeping with the engineering theme of lightweight technology, the new wheels are supported by a composite magnesium structure that reduces the weight of the steering wheel assembly by 10 percent compared to the former steel and aluminum structure.

For the first time, a multifunction steering wheel is standard on the 911 Carrera S Cabriolet and available on the 911 Carrera Cabriolet. This wheel allows the driver to operate audio, and navigation via controls mounted on the steering wheel.

A rotary knob on the left-hand steering wheel spoke controls audio volume, which can be muted by pressing the knob. A knob on the right-hand spoke accesses menu points on the Porsche Communication Management (PCM) system. Pressing the knob selects individual items. The two buttons on the lower steering wheel arm control the telephone.

In addition to the standard leather colors that match the rest of the interior, the multifunction steering wheel is available with wood grain or carbon trim.

More supportive seats are lighter and stronger

A new seat design includes a patented system engineered to better absorb vibration and thus to help keep the driver and front-seat passenger fresh and alert even on long trips. To better accommodate taller occupants, the shoulder area and width of the seat cushion have been increased. To accommodate taller drivers, the pedals have been moved 0.39 inches (10 mm) toward the front of the car.

The seats also feature higher side bolsters to provide support in situations of higher lateral acceleration through curves.

To help lower the car’s center of gravity, the seats are mounted 0.39 inches (10 mm) closer to the floor, providing the driver with a more dynamic seating position while also creating more headroom for taller occupants.

Again, lightweight technology has been employed in the seat structure, which is stronger and more stable while being some 6.1 pounds (three kg) lighter for each of the front seats.

Four seating options

The standard front seats are adjustable in six directions – fore and aft, height and the angle of the backrest. Height adjustment is made through a new mechanical step function positioned between the seat and the doorsill. Backrest angle is electrically controlled.

All-electric seats are available and adjustable in 12 directions, including the angle of the seat cushion and a lumbar support comprising four air chambers. These seats also have a memory feature. Sport seats with even greater lateral support both in the seat cushion and shoulder area also are available. These seats feature firmer padding.

A fourth variation are adaptive sport seats that combine the sports design with electrical controls. These seats have four-dimensional adjustment that includes fitting the seat bottom and backrest to the occupant’s body.

Larger instrument display

The five dials that comprise the instrument panel have been moved further apart to provide a larger display area for better readability. The faces of the dials are black in the 911 Carrera Cabriolet and have an aluminum finish in the 911 Carrera S Cabriolet.

The tachometer remains the large and center dial and continues to have a dot matrix display beneath the rev counter. The speedometer with integrated overall and trip odometers is just to the left of the tach while large gauge just to the right of the tach includes coolant temperature and fuel gauges as well as the clock. The oil temperature gauge is at the far left of the cluster with the oil pressure gauge at the far right.

The new gauges have white light-emitting diodes that provide enhanced illumination for night driving.

Sport Chrono Package Plus

A clock-style gauge mounted on top of the dashboard is part of the optional Sport Chrono Package Plus available on 2005 Porsche 911 Carrera Cabriolet and 2005 Porsche 911 Carrera S Cabriolet. The “Chrono� option allows the driver to engage more aggressively set electronic control maps for the Motronic engine management system, Porsche Stability Management (PSM), Porsche Active Suspension Management (PASM) and Tiptronic S transmission (on vehicles equipped with these options).

The revised Motronic maps strongly favor performance over comfort and provide even quicker engine response, not only on deployment but also on release of the throttle, as well as more abrupt gearshifts by the Tiptronic S transmission. PSM thresholds, including ABS settings, expand to allow more lateral slip before intervention. PASM switches to its firmer setting to provide more agility in cornering. However, in some instances, such as on wet pavement, a softer suspension setting can be advantageous so the driver using the “Chrono� package simply presses the PASM button to return to the normal damper settings.

The Chrono Package Plus includes a digital/analog stopwatch and lap-counting function (activated by a button on the stalk on the left side of the steering column) and uses the screen of the Porsche Communication Management (PCM) for graphic display and review for this information.

Revised heating, air conditioning and ventilation

To help keep the driver and occupants comfortable in all situations, the convertibles feature automatic climate controls with an interior air and pollen filter. The air guidance system has been revised to increase the output and performance of the air conditioning and heating system with larger pipes and improved side vents.

Climate controls are integrated into the center console along with switches for seat and rear window heating.

Standard PCM with upgraded audio equipment

Revised Porsche Communication Management (PCM) is included as standard equipment in both 2005 Porsche 911 Carrera and Carrera S Cabriolets. New features for PCM include a DVD-based navigation system as a separate optional module, located in the luggage compartment. This allows the CD drive on the PCM to be used exclusively for audio CDs.

Also standard on PCM is a new Sound Package Plus that includes nine speakers with three times the usual transmission area and an external analog amplifier for outstanding sound in all driving conditions. The system includes two .75-inch (19-mm) tweeters and one 2.76-inch (70-mm) midrange speaker in the instrument panel, two 3.94-inch (100-mm) midrange speakers and two 7.87-inch (200-mm) woofers in the doors and a 3.94-inch (100-mm) wide-band speaker in the rear section of the passenger compartment.

The external analog amplifier is located in the luggage compartment and supplies the woofers in the doors and the midrange speakers in the instrument panel.

A multiple CD changer is available as an option. Pre-wiring is installed in all 2005 Porsche 911 Carrera and Carrera S Cabriolet models for easy installation of a CD changer in the luggage compartment.

DVD-based navigation The upgraded and DVD-based optional n

avigation module is much faster than the former CD-based system and allows rapid availability of routes and map updating, as well as 23 zoom stages to a minimum resolution of some 55 yards (50 meters).

Optional Bose surround sound

The new Porsche 911 s are the first sports cars available with the Bose Surround Sound System that includes 13 speakers and a seven-channel digital amplifier integrated into the MOST light wave conductor that is part of PCM.

The heart of the Bose Surround Sound System is a digital amplifier with a 5 x 25 watt output and additional support from an integrated and external 100-watt switching terminal. Active electronic equalization adjusts the reproduction of sound to specific acoustic conditions within the car so all passengers enjoy a true experience.

The system includes Bose’s AudioPilot technology that automatically adjusts sound and volume to compensate for wind or road noise inside the vehicle. A special microphone in the steering column cover picks up such noises.

Speakers used in the Bose Surround Sound System are Neodym units that are more compact, lighter and have better performance than conventional speakers. A Neodym iron born magnet generates a magnetic field 10 times more powerful than a conventional speaker magnet. These speakers also weigh some 23 percent less than the speakers used in previous 911 models.

The Bose Surround Sound speakers include two .98-inch (25-mm) tweeters and one 2.76-inch (70-mm) midrange speaker in the instrument panel, two 3.15-inch (80-mm) mid-range speakers and two 7.87-inch (200-mm) woofers in the doors, two .98-inch (25-mm) tweeters and two 3.15-inch (80-mm) midrange speakers in the rear of the passenger compartment and one active subwoofer with two 5.12-inch (130-mm) woofers in the rear parcel shelf.

Increased storage area

The 2005 Porsche 911 Carrera and Carrera S Cabriolets feature expanded storage compartments and boxes. The capacity of the locking glove box has been increased to nearly 400 cubic inches (6.5 liters) and includes a rack to hold two CDs as well as a penholder.

Just above the glove box is a cup holder hidden behind a folding trim cover. When released, the left cup holder emerges in front of the central air nozzle in the instrument panel while the right cup holder rests in front of the front passenger nozzle.

The center console includes more than 90 cubic inches (1.5-liters) of capacity as well as a 12-volt outlet and a coin holder. This compartment automatically locks when the central locking system for the doors is activated.

Additional storage pockets are located in the interior door panels with covers that also serve as armrests.

Another large storage area is located behind the rear seats. Tipping the seat backs forward can expand this area.

Even the front luggage compartment is larger, offering 4.41 cubic feet (125 liters) of storage capacity.

Cayenne-style electronic network

The 2005 Porsche 911 Carrera and Carrera S Cabriolets benefit from a comprehensive electronic network like that introduced in the Porsche Cayenne sport utility vehicle. Thus the 911 assures complete and efficient exchange of data and electronic information by 29 control units throughout the vehicle through an internal high-speed network or CAN-bus (Controller Area Network) and light-wave MOST-bus (Media-Oriented System Transport) networks.

Without such electronic networking, features such as Porsche Active Suspension Management would not be possible. The software required for this purpose has been developed under Porsche’s leadership and represents one of the company’s core competencies.

In addition to quicker and more integrated electronic communication with a wider range of functions, this new electronic system is some 11 pounds (five kg) lighter than the system used in the 2004 model.

New guide-me-home lighting

Exterior lighting includes a guide-me-home feature that can be selected via the light switch. This feature turns the lights on when you leave the car. In addition to headlamps, fog lights, rear lights and licenses plate lights stay on for 30 seconds to allow the driver and occupants to see obstacles or puddles of water.

Long list of options

Included on the option list are Porsche Parking Assistance, which uses ultrasound to measure the distance and provides an audible warning to the driver.

Standard anti-theft warning system

The 2005 Porsche 911 Carrera and Carrera S Cabriolets feature a standard anti-theft warning system that uses a new radar sensor to maintain surveillance of the vehicle interior. Unlike some systems, this sensor is not affected by reflections from bright interior leather surfaces.

Substantial warranty

Every new model-year 2005 Porsche car sold in the United States and Canada is covered by a fouryear/50,000-mile (80,000 kilometer), bumper-to-bumper limited warranty, which includes Porsche’s roadside assistance program. The galvanized body and 26-step paint and anti-corrosion process enable Porsche to warrant each car against rust perforation for 10 years and unlimited mileage.

In addition, Porsche guarantees the paint finish for three years – also without a mileage limitation.

Porsche Cars North America, Inc. (PCNA), based in Atlanta, Ga., and its subsidiary, Porsche Cars Canada, Ltd., are the exclusive importers of Porsche sports cars and Cayenne sport utility vehicles for the United States and Canada. A wholly owned, indirect subsidiary of Dr. Ing. h.c.F. Porsche AG, PCNA employs approximately 250 people who provide Porsche vehicles, parts, service, marketing and training for its 203 U.S. and Canadian dealers. They, in turn, provide Porsche owners with best-in-class service.

Porsche Expands the Technology Envelope for 2005

Sports Chrono Package Plus lets the 911 driver dial in preferred performance parameters

For Porsche, the ultimate challenge is always to push the limits of possibility. From the company’s very beginning, Porsche has explored and expanded the limits of performance, through competition on the racetrack and with innovative technology engineered to enhance the driver’s daily experience on the road.

Throughout its proud history, Porsche has been respected for the dynamic quality of its vehicles and for the engineering expertise and technological innovations that make those vehicles so safe, so secure and, yes, so exciting to drive. Now, for the 2005 model year, an already impressive list of engineering innovations expands with the introduction of the Sports Chrono Package Plus.

Porsche Active Suspension Management for the 911

There are two versions of Porsche Active Suspension Management, one for the Cayenne sport utility vehicle and the other for the 2005 Porsche 911 Carrera and 2005 Porsche 911 Carrera S.

For 2005, Porsche Active Suspension Management is standard equipment on the 911 Carrera S and optional on the 911 Carrera and uses active damper technology to provide both a comfortable yet sporty suspension setup for regular driving and very aggressive settings for performance driving. Compared with the standard suspension, PASM lowers the entire car by 0.39 inches (10 mm). Further, by pressing a button on the center console, the driver can chose between normal and sport settings.

The normal setting provides a more comfortable damper setting that changes gradually to a sporting mode as the driver adopts a more dynamic style of driving. For example, when cruising down the freeway, the normal setup absorbs minor and medium bumps more smoothly than the standard 911 suspension.

On the other hand, the sport mode activates a firmer damper control map for agile, dynamic driving styles and minimizes body roll to the point that lap times in testing on Germany’s famed Nuburgring racing circuit were reduced an average of five seconds per lap compared to the standard 911 suspension setup.

Porsche Active Suspension Management for the 911 links adaptive dampers and a pair of accelerometers that track vertical movements of the body with a control unit. Active dampers have a similar structure as standard shock absorbers, but also have a bypass valve in addition to the regular opening in the main piston so oil flow can be increased or reduced as needed to infinitely adjust damping forces. In the event of a system failure, the valve closes automatically and PASM maintains its hardest position to provide the safest dynamic driving mode.

One accelerometer is mounted on the top of the right front damper dome and the other on top of the left rear dome. The control unit compares reading from these accelerometers with lateral acceleration, steering angle, road speed, brake pressure and engine torque to determine optimum damper control for each wheel.

PASM has five specially developed software modules to assure excellent performance in all driving conditions:

• The lane change module responds to fast movements of the steering wheel and instantaneously increases damper forces on both axles to better control lateral forces and improve handling in extreme dynamic situations.
• The vertical control module does two things: in the normal setting, it increases damper forces whenever vertical movement of the car’s body exceeds a certain threshold, for example, on a bumpy road; in the sports mode, the system slightly reduces the damping effect to maintain better wheel contact to prevent the car from “jumpingâ€ÂÂÂ� around while assuring good ride comfort.
• The lateral acceleration module increases damping effect through a turn as a function of road speed and lateral acceleration to enhance driving precision.
• The brake module responds as soon as the driver starts to apply the brakes and switches to a harder damping effect to reduce body “diveâ€ÂÂÂ� to assure faster transmission of braking forces to the road to optimize braking performance. Then, during brake application, the system switches to a softer control setting after a certain period, applying different forces to the front and rear axles as needed. This is particularly effective on bumpy roads, where it assures better surface contract and shorter stopping distances.
• The load change module switches damper control maps and establishes different damping forces on the front and rear axles in all-out acceleration, when the driver lifts off the accelerator or shifts gears. This prevents the car from developing too much “squatâ€ÂÂÂ� in normal driving. In the sport setting, the system briefly switches to a softer damper response to improve traction when accelerating on a bumpy road.

Sports Chrono Package Plus: Much more than a stopwatch, it sets higher dynamic parameters

A clock-style gauge mounted on top of the dashboard of the 2005 Porsche® 911® Carrera® or 2005 Porsche 911 Carrera S signals that this car is equipped with Porsche’s newest technological innovation: the Sports Chrono Package Plus.

While there are several sports cars available with a built-in stopwatch, Porsche’s Sports Chrono Package Plus does much more than record sprint or lap times. Of course, Porsche’s Sport Chrono Package Plus does include a stopwatch and lap-counting function, and uses the Porsche Communication Management (PCM®) system to provide graphic display of such information. But Porsche’s Sports Chrono Package Plus also allows the driver to engage more aggressively set electronic control maps for the Motronic engine management system, for the Porsche Stability Management (PSM), for the Porsche Active Suspension Management (PASM) and for the Tiptronic® S transmission (on vehicles equipped with these options).

By pressing a button on the center console, the driver engages Sports Chrono Package Plus to take driving dynamics to a standard never before available. Under Sports Chrono Package Plus, changes are effected to the gas pedal control lines, engine speed limiter, engine throttle butterfly, PSM, PASM and Tiptronic S.

When the Sports telltale lights up on the center portion of the gauge cluster, the driver knows that the E-gas control line has switched to a steeper configuration that puts the Tiptronic S in its manual mode, thus the throttle butterfly responds more quickly to movements of the gas pedal and the driver enjoys even more spontaneous response from the engine. Should the driver keep the accelerator pedal fully depressed without shifting gears, the engine speed limiter in gears 1-5 intervenes far more abruptly than in routine driving. Shifts become less oriented to comfort and the throttle butterfly closes faster when the driver lifts off the accelerator pedal, thus providing a more dynamic driving experience, more similar to the feedback a racer gets from a car on the track.

The operation and intervention of PSM also changes to provide greater agility. For example, when accelerating out of turn in the Sports mode, higher anti-spin control thresholds allow more slip from the rear wheels. This can result in even faster acceleration because PSM does not intervene as quickly. Likewise, other PSM thresholds, such as those that control the anti-lock braking system, also are raised to a level that allows more dynamic control by the driver before the system intervenes. And the particularly skilled driver retains the option of switching off the PSM system and taking manual control of the car’s dynamic direction.

Under the Sports Chrono Package Plus, the PASM also switches automatically when needed to a sports program that provides firmer suspension settings, reducing even further body lean through corners and enhancing contact between the tires and the road surface. However, there are circumstances, such as on wet or snowy roads, in which an aggressive driver knows that a “softer� suspension setting can enhance traction and thus the PASM button can be pushed to put the car in its normal setting even when the sports mode is active.

So the driver can graphically verify the improved dynamics of the 2005 Porsche 911 Carrera and 2005 Porsche 911 Carrera S equipped with Sports Chrono Package Plus, the driver can push a stalk attached to the left side of the steering column to record various route segment times, which can be reviewed graphically on the PCM screen.

The Sports Chrono Package Plus is just the latest in a long list of Porsche technological innovations available on 2005 models of the 911, Turbo or Cayenne® sport utility vehicle. Information on other technologies follows:

PASM for the Cayenne SUV

Porsche Active Suspension Management (PASM), a variable damping system, is standard equipment on the Porsche Cayenne Turbo and is optional on the Cayenne S and Cayenne.

On the Cayenne, PASM incorporates an air suspension system that provides extra ground clearance in rough terrain, automatically lowers the vehicle at highway speeds, and has a self-leveling feature that helps to provide a proper position regardless of passenger or cargo loads or the presence of a trailer. The air suspension incorporates six ride height levels, allowing a range of 4.56 inches.

PASM further adjusts damper forces in response to road surface conditions and each driver’s style. For example, under the rapid and powerful application of the gas and/or brake pedal, as when driving aggressively on twisting roads, or when driving with cautious movements on particularly rough terrain, PASM steadies body sway and dive motions by monitoring body movement through five accelerometers. As soon as the motion of the Cayenne’s body exceeds programmed limits, PASM intervenes and works to stabilize the vehicle by acting on specific dampers.

PASM also allows the Cayenne driver to select from Comfort, Normal or Sport modes. However, should a driver select, say, the Comfort mode but then operate the vehicle in a more sporting style, the system automatically switches to the Sport mode and makes the appropriate changes in damper settings.

Porsche cautions drivers that while PASM provides for extremely dynamic handling, no system can overcome the laws of physics.

Porsche Stability Management

Porsche Stability Management (PSM) helps keep a vehicle going in the direction the driver steers, whether on a dry paved road, a slippery road or even unpaved surface. PSM uses data from several sensor inputs to detect a loss of grip. The system reduces instability by applying brakes to individual wheels and, if necessary, by reducing engine power. PSM operates so quickly that most drivers will not notice its corrections.

PSM is tuned to the driving style and skills of Porsche drivers. Drivers who want total control of their vehicle can disengage PSM with a switch located on the dashboard. However, for purposes of safety, PSM automatically engages under braking and then disengages when the driver lifts off the brake. Porsche also cautions drivers that while the system provides a dynamic handling aid, no system can overcome the laws of physics.

With the introduction of the 2005 Porsche 911 Carrera and 2005 Porsche 911 Carrera S, a newest generation of PSM uses new anti-lock brake sensors that take their readings not from conventional wheel pulses but from multi-pole seats fitted directly on the wheel bearings. These improved signals allow more precise processing and control. Instead of conventional shaft valves, linear solenoid valves adjust brake pressure with nearly infinite precision.

To provide pressure more quickly, a new hydraulic pump is used and a pre-charging pump and its connections are eliminated, reducing system weight by 25 percent, or 6.6 pound (3 kg).

Another enhancement to PSM for 2005 gives the enthusiast driver more control over the system. As in previous years, PSM can be turned off through a switch on the dashboard but now PSM does not automatically reactivate when the brake pedal is depressed. Instead, the system reactivates only when the pedal is pushed hard enough to exceed the ABS control threshold on at least one front wheel. This change allows the enthusiast driver more dynamic freedom, including slight use of the brakes in curves.

Porsche Traction Management

Drivers might think that the laws of physics do not apply to Porsche Traction Management (PTM), the newest generation in four-wheel drive technology that comes standard on every Cayenne. PTM significantly influences the Cayenne’s dynamic performance by coordinating the vehicle’s outstanding power and torque, its sporty and agile handling, and its excellent driving dynamics with superior performance off the beaten track.

In normal conditions, PTM feeds 62 percent of the engine’s power to the rear wheels and 38 percent to the front wheels. This assures that the Cayenne has the same basic dynamic characteristics as the Porsche 911. However, through the use of a multiple-plate clutch, the Cayenne can vary the power split as needed, if necessary feeding 100 percent of the engine’s torque to the front or rear wheels.

The map-controlled front-to-rear lock and the optional rear axle differential lock not only respond to lack of traction on the front or rear wheels, but incorporate sensors to measure such things as vehicle speed, lateral acceleration, steering wheel angle and operation of the gas pedal. PTM determines the optimum lock on both axles and distributes drive power as actually required to the front and rear wheels.

Thus PTM acts as an intelligently networked electronic system that helps to provide stability and safe lane change behavior both at high speeds and when driving on snow and ice at moderate speeds. This innovation offers an impressive range of outstanding results, including:

• Excellent driving stability and traction in all situations, regardless of the frictional coefficient;
• Better steering provided by the front-to-rear differential lock opening up to avoid any understeer effect;
• A front-to-rear differential that ensures better control when driving to the limit;
• Enhanced directional stability and better road grip by operating the front-to-rear lock as required;
• Better traction by increasing locking action before the wheels start to spin.

Porsche Stability Management (PSM) remains consistently in touch with Porsche Traction Management (PTM), but intervenes only when the vehicle reaches its limits.

Masterminding essential systems such as ABS (Anti-lock Braking System), ASR (Automatic Slip Regulation) and ABD (Automatic Brake Differential), PSM cuts in immediately under critical over- or understeer conditions and tells PTM to open the locks to restabilize the vehicle by applying the brakes specifically on individual wheels.

The Cayenne successfully combines outstanding performance on the road with equally outstanding off-pavement abilities. Indeed, it is already a genuine master off the beaten track in its “basic� configuration, intelligent four-wheel drive enabling the Cayenne to easily cross light terrain without any adjustment of the traction systems.

On rough terrain, the Porsche Traction System uses the reduced-ratio gearbox featured as standard equipment. With its reduction ratio of 2.7:1, the reduction gearbox is ideal for even the most extreme off-pavement maneuvers, easily handling steep gradients and, in particular, downhill passes.

Activating the low-range mode by means of a toggle switch on the center console, the driver can automatically prepare several control systems for off-pavement driving conditions: PTM switches over to the reduced ratio for off-pavement requirements and changes to a special off-pavement control map activating the differential locks, PSM responds by setting ABS and ABD to a special traction mode for off-pavement motoring, and the air suspension featured as standard in the Cayenne Turbo automatically lifts the entire vehicle up to its off-pavement level.

Porsche is the first carmaker to offer this combination of systems all controlled by one central offpavement switch and thus significantly facilitating operation of these systems when driving under extreme conditions.

Porsche Side Impact Protection

POSIP (POrsche Side Impact Protection) is standard on all Porsches and provides the driver and front passenger with a broader scope of protection than conventional side airbags.

A special feature of POSIP is that this airbag system is able to ensure exemplary protection, even in an open convertible.

Housed in the door panel of Porsche sports cars, the airbag modules differ from conventional units through their large volume and airbag geometry. In a collision from the side, this ensures not only the usual protection of the torso, but also helps to protects the driver’s and front passenger’s head from hitting an obstacle at the side, regardless of the fore-and-aft position of the seats.

Because of the size of its interior, the Porsche Cayenne sport utility vehicle gets a special airbag system that includes front, side and head curtain airbags. In the Cayenne, 911 Carrera and Carrera S the side airbags have been placed in the backrests of the front seats. While providing protection for the driver and front-seat passenger’s heads, this separate airbag also helps to protects passengers sitting in the rear seat in the event of a side impact. This system is designed to provide protection even when a narrow obstacle, such as a pole or a tree, strikes the vehicle.

Variable-ratio rack-and-pinion steering

For the first time, the 2005 Porsche 911 Carrera and 2005 Porsche 911 Carrera S feature standard variable-ratio steering, a system that enhances the car’s agility on winding roads while retaining exceptional stability at higher speeds.

When the steering wheel is turned 30 degrees from its centered position, the steering ratio remains similar to that on the previous generation 911. This assures a smooth and calm driving experience, even on rough surfaces on which a driver might have a tendency to steer too much.

However, when the steering wheel angle exceeds 30 degrees the steering ratio becomes more direct, reducing the lock-to-lock ratio from its usual 2.98 to only 2.62. This gives the driver better control both on fast, winding roads and in slow-speed parking maneuvers.

Porsche Ceramic Composite Brakes

Because of their exceptional performance in extreme conditions, ceramic composite brakes were developed for use in high-level motorsports competition. Porsche was the first automaker to apply them for road use, with Porsche Ceramic Composite Brakes (PCCB®) included as standard equipment in the 2005 Carrera GT and the 2005 Porsche 911 Turbo S coupe and convertible.

Ceramic composite brake discs provide a 50-percent weight savings compared to conventional metal discs. This reduces unsprung weight, enhances shock absorber response and vehicle handling, and also improves fuel efficiency and thus contributes to reduced emissions.

Ceramic composite brake discs have an extremely hard surface that provides consistent frictional values throughout the deceleration process, even in braking from extremely high speeds and at high operating temperatures, such as those generated from repeated braking. But the system also provides benefits in low-speed situations. In the event of an emergency stop, PCCB technology does not require heavy pedal forces or outside technological boosting assistance to achieve maximum and immediate stopping force.

With cross-drilled discs and pads that are resistant to water absorption, the ceramic composite brakes provide superior response in wet conditions as well as dry.

Because of their hard surface and immunity to salt corrosion, Porsche Ceramic Composite Brakes have an extremely long operating life.

Porsche Ceramic Composite Clutch

With the introduction of the Carrera GT, Porsche launched the Porsche Ceramic Composite Clutch (PCCC®). Ceramic composite clutches were developed for use in motorsports at the highest levels of international competition. However, in such applications and for specific use on the racetrack, they often have short lives.

But by applying lessons learned through the development of Porsche Ceramic Composite Brakes, Porsche has created a new clutch design and configuration that applies ceramic composite technology to the public roads with a two-plate dry clutch made from a composite of carbon fiber and silicon carbide. This ceramic composite clutch is compact and light, but also strong and has an exceptional service life.

In the Porsche Ceramic Composite Clutch, the plates are only 6.65 inches (169 mm) in diameter, less than half the size of typical production car clutch plates, which can run as large as 15 inches (380 mm).

Because it is extremely compact and lightweight, the PCCC contributes to the Carrera GT’s incredibly low center of gravity. The PCCC’s low mass also has a very positive effect on the dynamics of the Carrera GT’s 605-horsepower (SAE), 5.5-liter V10 engine and its six-speed, transversely mounted transmission.

Tiptronic S transmission

Tiptronic S is Porsche’s version of an automatic transmission, and offers five forward gears for the 911 models and six for the Cayennes. The driver can shift gears manually by tipping the selector lever on the center console or by using toggle-style switches on the steering wheel. The driver presses the upper portion of the thumb switch or tips the center console shift selector forward to advance the gears, or presses the lower part of the thumb switch or tips the shift selector back to downshift.

One major advantage of the Tiptronic S is that it provides the driver with the option of intervening while the transmission is in automatic mode. The driver can move the thumb switch on the steering wheel and shift gears manually even though the gearshift selector lever in the center console remains in the automatic position. In such a case, the manual mode is activated for at least eight seconds, and this period is extended when the car is in “overrun� – for example, on a downhill grade, to capitalize on engine braking – or when the driver downshifts before the entrance to a curve and the car is under lateral acceleration as it negotiates the turn.

When in such a situation, the letter “M� appears in the right-hand instrument dial and the specific gear currently engaged also is displayed. At the same time, the transmission retains its kick down function so the driver can downshift again as needed. The transmission can downshift by as many as three gears when the driver steps hard and quickly on the gas pedal.

In automatic mode, Tiptronic S adjusts to various shift control maps based on the driver’s style of driving and the route. The range of shift points extends from a particularly economic mode activated whenever the driver prefers a calmer and more reserved style of driving (with the gears shifting up at an earlier point and engine speeds being reduced accordingly) all the way to a very dynamic, active mode (with the gears remaining in mesh for as long as possible when accelerating, using the engine's free-revving driving characteristics). The crucial factor in all cases is the driver’s foot on the accelerator: Moving the gas pedal quickly and dynamically, accelerating frequently with full power, the gearshift points change accordingly, switching if necessary to the most dynamic variant and vice versa.

Over and above its ability to recognize the driver’s style, Porsche Tiptronic S also features:

• A warm-up program that prevents the transmission from shifting up too soon, thus increasing the temperature of the catalytic converter as quickly as possible while allowing the engine to warm up smoothly and without any strain;
• An active gearshift that immediately moves the shift points to the most sporting and dynamic program whenever the driver presses the gas pedal quickly and dynamically;
• Suppression of upward gearshift in overrun when the driver’s foot suddenly lifts off the accelerator, for example, before entering a bend;
• Downshifting to the next lower gear to optimize engine braking when the brakes are applied;
• Increment upshift that delays shifting into a higher gear after an active downshift;
• Retention of gears in a bend to prevent upshift; and
• Hill recognition that retains lower gears as long as possible in uphill or downhill gradients.

To reduce the possibility of an improper shift when the Cayenne SUV is traversing rough terrain, the steering wheel switches are deactivated when the reduction gearbox is engaged. In this case, the driver can shift manually only by moving the shift lever on the center console. But the driver may not have to shift manually because Tiptronic uses gearshift control maps to ensure optimum power in rough terrain.

Another Tiptronic S feature in the Cayenne is a hill-holder function that prevents the car from rolling backward when setting off in a forward gear, even on a steep grade.

VarioCam variable valve timing

VarioCam and VarioCam Plus are Porsche’s patented variable valve timing and valve lift technologies. Originally developed for the Porsche 911 Turbo, they are designed to optimize each vehicle’s dynamic capabilities while properly managing the fuel consumption and exhaust emissions of such high-performance engines.

Similar technology can be found in every Porsche engine.

VarioCam refers to cam timing adjustment that can be either a one-step system, as on the Porsche 911 Turbo, or a fully adjustable vane cell system, as on the 911 Carrera models and the Cayenne models. VarioCam Plus adds valve lift control and is used on vehicles such as the Porsche 911 GT2.

VarioCam technology allows adjustment of the camshaft angle and is set to provide optimum performance for each Porsche engine. For example, in the Cayenne S and Cayenne Turbo, an adjustment of up to 25 degrees assures a beefy torque curve for the sport utility’s V8 engine.

With VarioCam, intake camshaft timing is fully variable through a wing-cell adjuster fit directly on the camshaft drive sprocket. Oil pressure is used to turn the position of the inner wing-adjuster wheel versus the outer sprocket. Because the intake and exhaust camshafts are driven directly via a roller chain, this system makes the conventional three-stage chain drive redundant between the crankshaft and the camshaft.

Porsche’s patented VarioCam responds quickly to any sudden need for power or, conversely, to a more reserved style of driving, say in city traffic. This is possible because of the way it makes precise adjustments to valve opening and closing times.

When running under part load, the intake camshaft is set to an earlier opening point. The residual gas remaining in the combustion chamber builds up maximum output through the small overlap in the opening and closing times. Maximum torque is provided by extended valve overlap and the earlier conclusion of the intake period.

VarioCam Plus not only adjusts camshaft position to provide continuously adjustable valve timing, but also varies valve lift and duration. This helps to flatten as well as smooth the torque curve while reducing emissions. The use of dual valve springs ensures reliable high-performance operation. Some have said that driving a Porsche equipped with VarioCam Plus technology is like having two engines in one vehicle: an engine that provides maximum horsepower and torque and another that provides quiet and efficient operation.

However, Porsche technology combines these characteristics into each engine. Even under cold starting, VarioCam Plus improves the engine’s characteristics by reducing emissions through suitable adjustment while the engine warms up.

While the engine is at idle, the small cams control valve lift and valve timing is optimized to keep any valve overlap to a minimum. The small valve lift serves to reduce friction and, thanks to the very short opening times, it significantly increases the charge motion while reducing emissions from any previous combustion within the chambers. The system also reduces fuel consumption and emissions by as much as 10 percent.

Under part load, valve lift shifts to a large overlap and the engine runs with internal recirculation of exhaust gases to minimize any throttle effect and to reduce fuel consumption.

Under full load, maximum torque and horsepower are ensured by a highly efficient gas charge cycle with minimum losses as well as an uncompromising cam contour and suitable adjustment of valve opening and closing times.

The system is controlled by engine management software, Motronic ME7.8 for the Carrera models and MY7.1.1 for Cayenne models, designed specifically for Porsche’s requirements. Engine speed, gas pedal position, engine oil and coolant temperature and even gear selection are monitored. The driver’s commands for horsepower and torque are compared with control maps. Within milliseconds, the computerized system responds and makes the proper adjustments.

Porsche Communication Management

Porsche Communication Management (PCM®) operates at the speed of light. Using Porsche’s MOST (Media-Oriented Systems Transport) technology, PCM uses light wave conductors to exchange multi-media data in every Porsche model in which it is installed. The big advantage of this technology is that it exchanges data without any loss of quality and at extremely high speeds. Among other features, this assures high-quality audio transmission for radio, CD changer and amplifier units.

Featuring a double audio tuner, CD player and trip computer, optional PCM provides a user-friendly design that includes a color screen and 12-digit keyboard. In the Cayenne, that screen is 6.5-inches across and provides the clarity of a 16:9 aspect ratio. The keyboard can be used for entering information such as radio station frequencies.

In addition, buttons beneath the display provide direct access to the individual menus such as trip computer (Trip button) or the navigation system (Navi button). Two buttons providing direct access to the Set (Set button) and Return (button with a bent arrow), thus avoiding the need to “jump around� from one sub-menu to another and wasting a lot of time in the process.

As well as improved radio reception, ensured by a modern double tuner consistently looking for the best frequency, the navigation module features the following outstanding highlights:

• Large choice of various navigation functions: Functions can also be presented on the map in the display, informing the driver of such facilities as restaurants, service stations or parking lots;
• On-demand road junction zoom: This function automatically enlarges road junctions in the active guidance mode, providing helpful support above all at dangerous points where a road junction is unclear.
• Map scroll: Benefiting from the wider range of map options, the user is able to shift the map display, scroll and position the map as required. This enhances navigation from the current location to the desired destination, checking out and memorizing a destination by means of a reticule display without having to enter the exact address.
• Tour planning: The tour planning function allows the user to enter and memorize routes with as many as eight destinations in a row. When setting out, the system will automatically guide the driver to the individual destinations on the way, in precisely the order recorded in advance. Further processing options on such extended routes are also possible, such as adding information, removing destinations, changing the order of destinations on the way or skipping a certain point.

2005 Porsche 911 Carrera and Carrera S Cabriolet Specifications