German tuner unveils ultimate Merc SL

Mercedes-Benz's in-house AMG tuning division already does a pretty fair job of fettling the three-pointed star's wares, but that doesn't mean there isn't scope to grasp the envelope and further stretch it to A4-like dimensions.

Witness the Carlsson CK63 RS, an amped-up take on Merc's SL 63 AMG -- hardly a shrinking violet in standard trim.

The makeover starts (or actually finishes) from the outside, with the showroom SL's gloss duco being rubbed off and replaced with 'Stealth Titanium Graphite' varnish, touted as "the far-most matt black colour that was ever produced".

"Matt black was not enough for us," said Carlsson spin doctor Stafan Müller. "We wanted a black varnish with such an extensive matt degree as it has never been seen before".

As proof of its dullness, Carlsson points out that matt varnishes usually attain a standard of 20 to 25 gloss units, but the particular colour, especially developed for Carlsson, has only five gloss units.

"And the colour shade still remains brilliant and is neither blurred nor milky," said Sascha Pfeffer, application technology manager at Standox, which supplies the varnish.

The CK 63 RS's upgrades extend to a revamped interior swathed in Alcantara and carbonfibre, while the remodelled bodywork gains bespoke front and rear bumper/spoiler/diffuser assemblies.

Also noteworthy (actually, downright curious) is what looks to be a hybrid of the Ford Mustang and Ferrari prancing horse badges emblazoned on the centre of the mesh grille.

The donor car's 6.2-litre V8 remains unchanged in terms of cubic capacity, but Carlsson's boffins have been able to ramp up peak power from 386kW to 441kW, while torque swells from 630Nm to a rippling 705Nm.

Its maker boasts of a 0-100km/h dash of 4.1sec, half a second faster than the AMG model, while v-max is limited at 325km/h instead of 250km/h. Carlsson claims its tailor-made aero kit provides high stability even at the speeds attainable by the CK 63 RS.

Boosting its grip/stability level is 'C-Tronic SUSPENSION', which is said to be an example of "intelligent lowering", as it enables the roadster to be lowered by up to 30mm.

Stopping power is via a Carlsson Carbon Composite braking package with six-piston calipers and 398x36mm carbon composite discs at the front and four-piston calipers and 330x35mm discs at the rear.

The wheel/tyre package is no less formidable, with Dunlop SP SportMaxx rubber wrapped around forged Carlsson 1/16 Ultra Light wheels sized 9.5x20 inches at the front and 11x20 inches at the rear.

Naturally, no tarted-up special is complete without gullwing doors these days, and the Carlsson doesn't disappoint in this respect.

The price, you ask? Not that it's likely to be available here but, for what it's worth, the Carlsson CK 63 RS costs a piffling 272,500 euros ($555,000) in its home market.