The 4.0-liter V-8 for the first time is fitted with a pair of twin-scroll turbochargers, resulting in 563 horsepower and 553 lb-ft of torque in the basic, non-S model. The sprint from zero to 60 mph takes a mere 3.4 seconds, according to Mercedes, and top speed is limited to 155 mph. In the E63 S, engine output reaches a new high of 603 horsepower and 627 lb-ft, the latter delivered on a plateau that stretches from 2500 to 4500 rpm. The S reaches 60 mph in a factory-estimated 3.3 seconds, with its top speed capped at 186 mph.