The most powerful production SLK of all time, the new 2012 SLK 55 AMG, has arrived in Britain and is available for to order with an on-the-road price of £54,950 (equal to US$84,630 / €66,200).

Lying under the hood of the AMG-branded SLK is a naturally aspirated, direct-injection V8 engine with a displacement of 5.5-liters that produces 421-horses at 6,800rpm and 540Nm (398.2 lb-ft) of peak torque at 4,500rpm.

A seven-speed AMG SPEEDSHIFT 7G-TRONIC PLUS automatic transmission drives the rear wheels with Mercedes laying claims to a 0-62mph (100km/h) sprint time of 4.6 seconds and a restricted top speed of 155mph (250km/h).

The roadster model’s combined fuel economy is 33.6mpg UK, with CO2 emissions of 195g/km.

Among other standard features, the SLK 55 AMG comes equipped with Nappa leather upholstery, 18-inch five-spoke alloy wheels, an Intelligent Light System, COMAND Online with Media Interface and a DAB digital radio.

On the options list there’s a special AMG Performance Package with revised suspension and brakes with a rear differential lock (£4,105) and the AMG Driver’s Package that removes the speed limited and includes attendance at an AMG ‘Power and Passion’ driver event (£2,755).

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