2012 Mercedes SLK55 AMG To Get New 5.5-litre V8

AMG is working on an ultra frugal V8 engine that will power the upcoming SLK55 AMG. The 5.5-litre naturally aspirated V8 is capable of churning out a healthy 416bhp (310kW), while returning close to an impressive 7.0L/km. Even without the aid of turbochargers, the engine will produce 45 more horsepower (34kW) than its predecessor. Torque is rated at 540Nm.

The trick? The AMG Cylinder Management System. It draws on Mercedes’ F1 know-how and uses a fuel-saving system that deactivates 4 cylinders under lighter loads. Together with start/stop technology, CO₂ emission is down to just 199g/km.

The sweet thing about all these is these features can be activated at any time, via a button called ‘Controlled Efficiency’, located on the transmission tunnel. The system is activated between 800 – 3,600rpm and reduces torque to a minimum of 230Nm. It will switch back to 8 cylinders seamlessly in just 30 milliseconds.

This should be enough to propel the SLK55 AMG from 0 – 100km/h in under 5 seconds. These figures will put it in the league of the forthcoming BMW Z4 M and the Porsche Cayman R, while outperforming both in terms of efficiency.

The 2012 Mercedes-Benz SLK55 AMG will be unveiled at the 2011 Frankfurt Motor Show in September.