First look: Fastest-ever 911 breaks cover

PORSCHE has released details of the fastest road-going 911 ever.

The fire-breathing 911 GT2 will be presented at the Frankfurt Motor Show this September and will arrive in Australia next March with a price of $425,700.

Porsche was planning to hold on to all the details and images of the new GT2 until closer to the show, but decided to release them early after pictures of the supercar were leaked last week.

The images suggest the GT2 will be meaner than all 911s to come before it, but it is the technical specifications that will really send hearts racing.

The GT2 runs the same basic twin-turbo 3.6-litre six-cylinder boxer engine as the regular 911 Turbo, but Porsche engineers have upgraded the turbochargers for even more punch.

That means the GT2 belts out an extra 37 kW for a tyre-searing total of 390kW achieved at 6500 revs.

The torque total is also up by 60Nm over the 911 Turbo for an impressive maximum of 680Nm between 2200 revs and 4500 revs.

Like the regular 911 Turbo, the GT2’s turbos feature variable turbine geometry to virtually eliminate turbo lag.

The GT2 is 145kg lighter than the standard 911 Turbo which is one of the reasons it can blast from 0-100km/h in just 3.7 seconds.

For the record, the 911 Turbo takes 0.2 seconds longer to manage the same sprint.

Top speed of the GT2, for those with access to an autobahn or a racetrack, is just below warp-speed at 329km/h, which is 19km/h faster than the 911 Turbo.

You could expect such a car to return terrible fuel economy figures, but Porsche said the GT2 uses 12.5L/100km of combined driving when tested to the New European Driving Cycle or NEDC formula.

The upgrades to the turbochargers include larger compressor wheels and improved turbo housings allowing boost pressure to be raised, although Porsche will not specify the pressure figure.

The GT2 also features a special expansion-type intake manifold that Porsche said keeps the temperature of the fuel/air mixture lower than in the equivalent 911 Turbo. It claims this system means that engine uses 15 per cent less fuel when operating under full load.

Porsche has fitted the GT2 with a rear silencer and tailpipes made of titanium as standard. Titanium is much more expensive than stainless steel, but is also about 50 per cent lighter.

The German carmaker has also fitted the GT2 with brakes that use composite carbon fibre/ceramic discs, which cut weight by 20kg per car compared to regular discs made from cast-iron.

Light alloy wheels, 19-inch in size, are standard and come fitted with 235/35 tyres at the front and 325/30 at the rear.

The GT2 runs a large air intake at the top of the front bumper and there are vertical gill vents at either side of the rear bumper.

Porsche has also fitted the meanest 911 with a massive twin-deck rear spoiler.

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