Mercedes chose this weekend to unveil the all-new SLK 55 AMG, the most powerful SLK ever, ahead of its official debut at the IAA.

As we’d confirmed before, the new Mercedes SLK 55 AMG is powered by a non-turbo version of the the new bi-turbo V8 that powers the bigger stuff, CLS63 and S63 for example. It might have lost its turbos, but it still has plenty of power to deliver.

The 5.5 liter M152 engine makes 422 PS and 540 Nm of torque, which enables the car to go from 0 to 100 km/h in 4.6 seconds and reach a limited top speed of 250 km/h. So in terms of performance, it’s way over the top. But what makes it really special is the economy features, that makes it one of the most efficient V8s currently in production.

This V8 has a clever AMG Cylinder Management cylinder shut-off system which depending on the driving condition can automatically deactivate two or four of the eight cylinders. That in combination with the mode “C” – Controlled Efficiency in the AMG SPEEDSHIFT PLUS 7G-TRONIC auto transmission, and the stop/start function give the car an average fuel consumptoin of 8.4 liter per 100 km which is astonishing for a car with level of performance.

As for the looks, the SLS-inspired design might not look all that good in the pictures, but it’s actually fab if you see it in person, and new AMG body kit only makes it better. We absolutely love the interior, with the two-tone leather upholstery and that awesome new steering wheel covered with Alcantara, it’s just very welcoming for a performance-minded driver.

The 2012 SLK 55 AMG is of course fully loaded with items like the Magic Sky Control roof, Pre-Safe system and DISTRONIC PLUS, as well as NECK-PRO crash-active head restraints, three-stage ESP and also ATTENTION ASSIST drowsiness detection.

And the price for all this, 72,590 Euro in Germany. The car will debut in Frankfurt Motor Show in September, and will go on sale early next year.

For now enjoy the pictures: