(2005 – 2008) Porsche 911 Carrera Cabriolet – Ultimate Guide
Just a few months after the introduction of the 2004 911 (997 series), the convertible version was released. The release of the 997 911 Carrera Cabriolet marked the first time since 1977 that Porsche has given the convertible 911s the same engines as their Coupe siblings. The base 997 Carrera Cabriolet gets the 3.6-liter flat six-cylinder engine with 321 bhp and 273 ft lbs of torque.
The convertible version for both Carrera and Carrera S was developed at the same time with the coupe. Thus, the engineers installed on the coupe some reinforcements needed for the cabriolet. As usual, most of the body parts from the open-top version were carried-over from the coupe. The platform was strengthened to act as a chassis. The convertible was only seven kilograms (15.4lbs) heavier than the coupe, which made it as fast as the closed-version. It was really the first time in 911 history that the cabriolet model gave up little performance or structural integrity compared with the coupe version, the upside being open-air sports-car motoring.
For the first time, the cabrio is introduced with a choice of two engines. The 911 Carrera is powered by 325 horsepower, 3.6-liter flat-six, while the Carrera S cab gains a bored-out 355-horsepower, 3.8-liter version of the six. A five-speed Tiptronic transmission is available, but we love the new six-speed manual gearbox with shorter throws. With the top closed, top speed is the same as the coupe at 177 mph. Extensive streamlining of underbody components is said to reduce lift to near zero. As an added aero touch on the cabrio, the deployable rear spoiler rises 0.8 inch higher than on the coupe.
Porsche shaped the insulated softtop with aerodynamics in mind, so the cabriolet achieves the same 0.29 coefficient of drag as the coupe, which helps keep the performance in line with the Coupe. The carefully designed convertible top is even designed to handle colder climates and yet still only weighs 93 pounds – including all of its system components. The lightweight top also helps 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-in-white 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.
A cool feature for the maniacs who like dancing and driving in the rain, the 997 Carrera Cabriolet has water ducts above the doors to prevent rainwater from dripping down inside. 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. And if droplets turn into full on monsoon, 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 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.
Inside, the Carrera Cabrio featured the same options as the coupe, plus the wind deflector. That allowed a normal conversation even with the top down at highway speed. To cover or uncover the car, the electric system needed only 20 seconds at speeds up to 50 kph (31 mph). To protect the occupants, the 997 cabriolet offered reinforcedac bars and six airbags.
Most of the chassis hardware on coupe versions of the Carrera and Carrera S carries over to the cabriolet–standard PSM stability control, 18-inch wheels, and vented, cross-drilled discs on the Carrera and PASM active damping, 19-inch wheels, and larger discs on the Carrera S. Even the optional ceramic brakes and Sports Chrono Package translate over to the new cabrio. While spring rates of the conventionally sprung Carrera and PASM-equipped Carrera S cabrios remain essentially the same as their coupe counterparts, the cabrio’s suspension tuning is shaded more toward comfort and avoiding spikes that might otherwise excite its open-top structure. Porsche claims the 997-based cabrio is five percent stiffer in torsion and nine percent more rigid in bending than the 996 cabrio. Softer engine mounts allow the entire drivetrain to function as a tuned damper.
The Carrera Cabriolet was updated for the 2009 model year with the rest of the lineup. This first version was known as the Porsche 911 Carrera Cabriolet (997) while the updated was known as the Porsche 911 Carrera Cabriolet (997.2).
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 911s 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 Porsche 911 Carrera Cabriolet and 182 mph (293 km/h) for the Porsche 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.
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.
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 Porsche 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 become 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.
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.
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.
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 Porsche 911 Carrera S Cabriolet and available on the Porsche 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 Porsche 911 Carrera Cabriolet and have an aluminum finish in the Porsche 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.
The upgraded and DVD-based optional navigation 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 911s 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 4.41cubic 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.