We’ve already brought you the news on the 2012 Mercedes-Benz SLK 55 AMG, but after an early leak over the weekend, the German company came out with an official release and plenty of photos detailing its powerful roadster model.

To recap, at the heart of the latest SLK 55 AMG lies a newly developed AMG 5.5-litre naturally aspirated V8 engine featuring cylinder shut-off that churns out a peak output of 422HP and maximum torque of 540 Nm in European specification. The North American market model is rated at 415HP and 398 lb-ft.

The SLK55 AMG accelerates from zero to 100km/h in 4.6 seconds (0-60 mph in 4.5 seconds), and reaches an electronically limited top speed of 250km/h (155 mph).

According to Mercedes-Benz’s preliminary estimates, the hardtop roadster consumes 8.4 litres of fuel per 100 kilometres on average (equal to 28.0mpg US and 33.6mpg UK), and emits 195 grams of CO2 per kilometrer. These figures are 20 percent and 30 percent lower respectively than those of its predecessor.

Power is sent to the rear wheels via a seven-speed AMG SPEEDSHIFT PLUS 7G-TRONIC automatic transmission which features three transmission modes: “Controlled Efficiency” (C), Sport (S) and Manual (M).

Other upgrades to the SLK 55 AMG include the AMG sports suspension with Torque Vectoring Brakes and AMG Direct-Steer system, an AMG-exclusive 3-stage ESP, 18-inch alloy wheels wrapped around 235/40 R 18 (front) and 255/35 R 18 (rear) tires, and for the first time in an AMG model, a sports exhaust system featuring an exhaust flap on each side.

As a proper AMG model, the flagship SLK also sports an aero kit and numerous interior upgrades such as AMG-specific analog clock featuring an IWC design, flattened top and bottom steering wheel and body-hugging seats.

Mercedes-Benz will also offer several optional features including an AMG Handling Package with a stiffer suspension, a rear axle differential lock, two-piece brake discs at the front and a three-spoke AMG Performance steering wheel finished in premium leather with Alcantara inserts in the grip areas.

The new SLK 55 AMG is scheduled to arrive in showrooms in March of 2012, with prices in Germany starting at €72,590. U.S. pricing has yet to be announced.

PHOTO GALLERY