Following the official unveiling of the new generation Porsche GT3, its more track-focussed sibling has been spied at the Nürburgring recently, testing alongside the current model.

2009 Porsche GT3 RS spied

Mechanically identical to the standard GT3, the RS or Rennsport model is lighter, stronger and more aerodynamic thanks to unique additions such as a polycarbonate rear window, carbon fibre hood, rear wing and roll cage.

While this prototype model wears a rather ordinary black exterior finish, the final production version will keep the trademark "GT3 RS" side sticker and special coloured wheels, decorative stripe, contrast-painted outside mirrors and rear wing endplates.

2009 Porsche GT3 RS spied

The GT3 RS has always been an anomaly, featuring an unassuming normally-aspirated 3.8-litre flat-six engine in its latest guise - hardly the credentials of a supercar - however Porsche has managed to extract an impossible 320kW from this engine.

The result is zero to 100km/h in around 4.0 seconds - fractionally quicker than the standard GT3 - and a top-speed of 311km/h.

2009 Porsche GT3 RS spied

A rear shot of the prototype explains at least part of its performance capabilities, with the massively wide tyres on the rear helping immensely with traction.

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