AMG Market News/SOURCE: MBUSA, MONTVALE, NJ: Mercedes-AMG has developed a new 5.5-liter V8 engine  which combines powerful eight-cylinder performance with the economical fuel consumption of a four-cylinder. This unrivaled efficiency is achieved thanks to the AMG Cylinder Management cylinder shut-off system developed exclusively by Mercedes-AMG.  Just like powerful, 750 hp  eight-cylinder Formula 1 racing engines,...