Powerful eight and twelve-cylinder engines are a traditional strength of AMG ? and no less so than with the S 63 AMG and the S 65 AMG, the S-Class top-of-the-line models. The S 63 AMG is powered by a high-revving V8 naturally aspirated engine developing 386 kW/525 hp, the S 65 AMG comes with a biturbo V12 engine that delivers 450 kW/612 hp. Despite no changes having been made to the engine and performance values, it has still been possible to reduce fuel consumption and CO2 emissions of the two high-performance saloons.