PORSCHE has kicked off its 50th anniversary celebrations by opening a fresh chapter in the arena of high performance sports cars with its new 911 GT3.

Back in 1999, the model set a benchmark for road-going sports cars with the fastest ever production car lap of the famous Nurburgring-Nordschleife circuit. Since then some 14,145 GT3s have been built.

Now, the fifth generation 911 GT3 has been unveiled at the Geneva Motor Show and will cost from £100,540 when it hits the streets in November.

The engine, transmission, body and chassis are all new, the powertrain comprising a 3.8-litre flat engine developing 475bhp, a PDK double-clutch gearbox and high-traction rear-wheel drive.

The six-cylinder engine is based on the one fitted in the 911 Carrera S, but shares only a few common parts, while the dual-clutch gearbox is another feature specially developed for the GT3.

Porsche is also using active rear-wheel steering for the first time whereby, depending on speed, the system steers in the opposite or same direction as the front wheels to improve agility and stability.

Acceleration is from 0-62mph in just 3.5 seconds, and 124 mph in less than 12 seconds, while the top speed of 195 mph is reached in seventh gear of the PDK transmission.

The Nurburgring lap time is even more impressive, the new GT3 completing what's generally regarded as the world's most difficult track, in less than 7:30 minutes.

It's a credential particularly relevant for the new model as around 80 per cent of 911 GT3 customers also drive their cars on race tracks.