Just when you thought gull-winged cars had reached their apotheosis, Mercedes goes and does an SLS GT3.

You, the ordinary person, can actually buy one of these, should you have the money and the time to gallivant around the globe racing folk. Weirdly, there's no word on the price, power or weight though.

That's because the FIA has to determine the specific lard and poke of the GT3 cars, so that the grid is nice and fair. It's reasonable to assume that the 563bhp of the standard car's 6.2-litre AMG V8 will get a little hike. And it'll certainly be lighter than that car's 1,620kg.

On the money front, a Porsche 911 GT3 R is about £250,000 and Mercedes claims the SLS will have a 'comparatively favourable cost structure'. It goes on sale in autumn.

So what's the difference? Much of the interior is stripped out, and what's left is swathed in carbon fibre. There's an open topped Alcantara (or maybe real suede) wheel with a single digital display in front of it. The centre console houses all kinds of race-related buttons, including one for the fire extinguisher marked 'holy crap!'

And holy aerodynamics, Batman! This thing is slippery. The bodywork gets a major widening and smoothing so it cleaves the air more readily. It's wider, with vents on the wheelarches, a completely smooth under tray, a big rear diffuser and a lower front splitter. The wing is adjustable for yet more downforce.

The suspension is fully adjustable too, both the spring and dampers. And you can even widen the track a little. The twin-clutch transmission of the standard SLS is dumped for a six-speed sequential item with paddles.

Unsprung weight is lowered with lightweight alloys, and the brakes are new, with massive perforated steel discs.

Mark Nichol - 1 Apr 2010