Apparently, the 612bhp Mercedes-Benz SL 65 AMG is underpowered for some people. Just as well then that the German tuning firm, Brabus, has come up with a suitably endowed alternative, the 720bhp Brabus SV12 S Biturbo Roadster...

Brabus claims that this iteration of the current SL-Class is the "world's most powerful roadster" outdoing the likes of Pagani's 650bhp Zonda F Roadster and even Lamborghini's mighty Murcielago Roadster. Performance is suitably impressive, with 0-62mph in a (traction limited!) 4.0 seconds, 0-124mph in an incredible 10.9 seconds and an electronically-limited top speed of 217mph (350km/h). Peak torque of 974lb.ft is available from just 2100rpm, ensuring warp-factor acceleration in any gear at any speed.

The regular, 5.5-litre 12-cylinder engine is extensively modified with a new billet steel crankshaft, larger cylinder bore, pistons and connecting rods. The conversion also includes re-machining the cylinder heads and fitting them with new camshafts. Naturally, the twin turbochargers are replaced with bigger items and the exhaust catalysts are thrown away in favour of low back pressure versions. The result is, according to Brabus, a serious powerhouse that also manages to be clean and refined.

Styling modifications are modest given the performance on tap. New bumpers front and rear and restyling of the front wings are topped off by a range of chunky alloy wheels, the largest of which are 20 inches in diameter. Improving the car's handling, as well as its stance is an update to the car's electronic damping system to allow the SL to sit 15mm lower. The massive new brakes should haul the car down from speed safely, but also look great.

Inside, Brabus customers can customise their car according to taste. Some of the more eye-catching options are carbon-fibre door sills with illuminated Brabus logos and sport steering wheels with heated rim and shift paddles for the automatic gearbox. Also available is a speedometer with a 360km/h dial and carbon-fibre interior trim in various colours.

The price? Well, if you have to ask... Every car is different. Click on the Brabus logo to visit the official website. We expect to see the Brabus SV12 S Biturbo Roadster at the Paris Show next month.

Shane O' Donoghue - 16 Aug 2006