With the manual transmission the Turbo Cabriolet accelerated to 60 mph (96 kph) in a mere 3.8 · seconds, 124 (200 kph) in 12.8 sec

With the manual transmission the Turbo Cabriolet accelerated to 60 mph (96 kph) in a mere 3.8 seconds, 124 (200 kph) in 12.8 seconds with a top track speed of 193 mph (310 kph). It is worth noting that Porsche's experienced test drivers accelerated to 60 mph 0.3 seconds more quickly with a Tiptronic S-equipped car than in one with a manual transmission. This is another example of Porsche's engineers bringing higher levels of performance to a broad range of skilled drivers. The Turbo Cabriolet is also certified as a Low Emissions Vehicle, category two (LEV-II) thanks to its engine's efficiency. Besides the twin turbochargers, the 3.6-liter boasts Porsche VarioCam Plus variable intake timing and lift system under the purview of its Motronic® engine controls. Aerodynamically efficient and stable Like its Turbo Coupe sibling, the '08 Turbo Cabriolet boasts a distinctive and aerodynamically efficient body shell with a coefficient of drag of only 0.31 when its soft top is closed. In addition, this third generation Turbo Cabriolet marks the first time that Porsche engineers were able to match the extremely low lift coefficients of the Turbo Coupe, when the Cabriolet's roof is closed. Maximum high-speed stability is attained thanks to the split rear wing which automatically extends 2.56 inches (65 mm) when the vehicle is moving at approximately 75 mph (120 kph). This feature, unique to the Turbo Cabriolet, ensures maximum high-speed downforce on the rear axle for added driver confidence. Knowing full well that electronic controls and aerodynamic aids need a solid base upon which to work, Porsche engineers created an extraordinarily stout body structure for the Turbo Cabriolet. The 2008 911 Turbo Cabriolet boasts a class-leading torsional stiffness of 9000 Nm/degree. The benefits of such structural rigidity extend well beyond crisp handling and smooth ride to occupant protection. The car's A-pillars and windshield frame are strong enough to serve as a front rollbar. This is complemented by a rear rollbar which automatically deploys from behind the rear seats in the event of a rollover. The Cabriolet's occupants are further protected in case of an accident by six airbags: dual frontal airbags as well as two seat-mounted front thorax airbags and door-sill mounted head airbags. Porsche firmly believes that accident avoidance is the ultimate safety feature. The new 911 Turbo Cabriolet, like the Turbo Coupe, boasts awesome stopping power, thanks to 13.78-inch (350 mm) diameter rotor disc brakes at all four wheels. The front rotors are internally vented and are clamped by six-piston, fixed calipers. The rear rotors stopped by four-piston fixed calipers. For those drivers wanting additional braking performance, the Turbo Cabriolet is available with Porsche Ceramic Composite Brakes (PCCB). Added features, not weight Despite the body's rigidity, Porsche engineers minimized its mass. The Turbo Cabriolet, with manual gearbox, weighs just 155 pounds (70 kg) more than its Coupe counterpart. Careful design and construction of the Cabriolet's folding top helped with the weight savings. The roof is made of fabric and lightweight metal, and the roof assembly weighs only 93 pounds (42 kg).