Geneva motor show 2010: Porsche Cayenne hybrid

Hot weather testing of the new Porsche Cayenne Hybrid has finished just over a month before the SUV is unveiled at the Geneva motor show on 2 March.

Developed in conjunction with the forthcoming Volkswagen Touareg Hybrid, the new Cayenne S Hybrid uses Audi’s supercharged 3.0-litre V6 petrol engine with 325bhp and 324lb ft. It is assisted by an electric motor with 38kW and 184lb ft. Combined, the two produce 375bhp – just 20bhp shy of the Cayenne S’s 4.8-litre V8.

See the Porsche Cayenne hybrid test pictures - including the first pictures of the car's interior

Greg Kable blog - First impressions: on board the Porsche Cayenne Hybrid

The battery is mounted under the boot floor and provides enough capacity for the car to run on electric power alone, although only for 1.2 miles and at under 31mph.

Unlike standard petrol-engined versions of the new Cayenne, which continue to use a multi-plate clutch to apportion drive, the Cayenne S Hybrid and Cayenne S Diesel use a lighter and more easily packaged Torsen four-wheel drive system similar to that used in the Audi Q7.

And in a departure from rival hybrid systems, the petrol-electric drivetrain developed by Porsche and Volkswagen decouples the eight-speed automatic gearbox from the engine on a trailing throttle at speeds up to 98mph.

“It’s a process that brings added fuel saving effects. We like to refer to it as sailing,” said Cayenne project head Michael Leiters. He also said that a similar arrangement will be used on the Panamera S Hybrid, due out later this year.

Despite possessing a 0-62mph time of just 6.5sec and a towing capacity of up to 3500kg, the Hybrid is said to return an impressive 34.5mpg, making it the most fuel-efficient model in the entire Porsche line-up. CO2 emissions are 193g/km.

Inside, the touch-screen monitor provides instant readouts of the operation of the petrol-electric driveline, together with historic data showing the percentage of electric drive used in five-minute intervals for the previous half hour.

The hybrid will join the rest of the new five-vehicle Cayenne line-up when the car is launched in the UK in May.

Autocar has also ridden in the new Cayenne Turbo during development testing. Read the full story and see the pictures here:

Porsche Cayenne - exclusive test

Greg Kable

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