After months of teasing, Porsche finally presented the four-door Panamera to the world public.

Unveiled at the Shanghai Auto Show in China, the new Gran Turismo enters the marketplace on 12 September 2009, and joins the Boxster roadster, Cayman coupe, iconic 911 sports car, and Cayenne all-wheel drive in the Porsche product portfolio.

The Panamera is making its debut with a normally-aspirated 300kW V8 petrol engine and a twin-turbocharged 373kW V8 petrol engine, and in both rear-wheel and all-wheel drive chassis configurations. A six-cylinder petrol engine and hybrid-powered derivatives will join the range later.

The Panamera offers the low and sleek silhouette that is typical of a Porsche, measuring 4.97m in length but only 1.42m in height, but these dimensions cloak the fact that there's space for four people inside.

Porsche's first four-door GT introduces five innovations to the luxury performance car class – among them the first engine Start-Stop system in conjunction with automatic transmission, air suspension with additional air volume available on demand in each spring, as well as active aerodynamics with an adjustable, multi-dimensional extending rear spoiler on the Panamera Turbo.

All models in the Panamera range come with Porsche Direct Fuel Injection engines, low-friction drive systems, and optimised lightweight bodies.

The rear-wheel drive Porsche Panamera S is offered with a six-speed manual gearbox. The seven-speed Porsche Doppelkupplungsgetriebe (PDK) double-clutch transmission is available as an option. The Panamera 4S and Turbo have four-wheel drive and feature the PDK gearbox as standard. The active all-wheel drive system is controlled by Porsche Traction Management (PTM) via a multi-plate clutch that adjusts the engine power distribution between the front and rear axles for increased grip and agility.

Moving to the suspension, there's a choice between steel springs or adaptive air suspension with a fully-controlled damper system. Depending on the preferred individual style of motoring or current traffic conditions, the driver can choose to emphasise a particularly comfortable or an especially sporting set-up conveniently at the touch of a button.

Every model offers a full leather interior, Porsche Active Suspension Management (PASM), Bi-Xenon headlights, rear ParkAssist, tyre pressure monitoring, automatic dimming rear view mirrors, Porsche Communication Management with touch-screen satellite navigation and audio controls, and a Bluetooth telephone module – complete with cordless handset for use by rear seat passengers.

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