At the heart of the Performance SUV Coupé is the AMG 4.0-litre V8 biturbo engine, which has been electrified here with an EQ Boost starter-alternator and a 48-volt on-board electrical system to deliver a particularly immediate response at start-up. The base model delivers an output of 420 kW (571 hp), the S variant an impressive 450 kW (612 hp).