New Mercedes-AMG S63: V8 super-PHEV packs 791bhp

The combination of a motor and a battery gives the S63 the capability to travel short distances on electric power alone. In Electric mode, it delivers up to 188bhp and 236lb ft of torque along with official WLTP economy of 2.90 miles per kWh and a claimed electric-only range of 20.5 miles.

As a result of the electrification measures, offical fuel consumption has been more than halved. The new S63's WLTP average of 64.2mpg beats that of the long-wheelbase S63 it replaces by 32.5mpg, despite all that added weight.

The 400V battery consists of 1200 cells and uses liquid cooling to maintain optimum operating temperate. Its energy capacity is more than double that of the battery used by the GT 63 S E Performance. It can be charged at rates of up to 3.7kW by an AC charger.

Additionally, the driver can choose between four stages of energy regeneration, the highest of which recovers kinetic electricity produced during braking and on the overrun at up to 90kW.

Mercedes-AMG has given the new S63 greater visual differentiation from other S-Class models than its predecessor.

Among the exterior styling changes made to the standard seventh-generation S-Class is a new-look front bumper and an AMG-specific Panamericana front grille with vertical louvers. 

An AMG emblem has replaced the Mercedes-Benz star on the bonnet, while the rear receives traditional S63 styling touches, including a new-look bumper with an integrated diffuser and trapezoidal tailpipes. The standard wheels are 21in in diameter.

The sporting theme continues inside with an AMG Performance steering wheel, AMG graphics for the digital instruments and selected infotainment functions, AMG-embossed upholstery for the front seats and AMG-specific trim for the dashboard, among other elements.

The S63 receives a reinforced body with what Mercedes-AMG describes as an “aluminium stabiliser” under the combustion engine, as well as an additional cross-brace between the front suspension towers. It also claims that a carbonfibre-reinforced plastic compartment used to accommodate the battery within the floor of the boot also adds rigidity to the rear.

Underneath, AMG Ride Control+ suspension with air springs and variable damping control provides automatic self-levelling and an automatic lowering function at speeds above 80mph for added aerodynamic efficiency.

The S63 also receives AMG Active Ride Control stabilisation with electromechanical anti-roll bars as well as rear-axle steering of up to 2.5deg.

Mercedes-AMG is yet to confirm pricing for the S63 in the UK, but with the GT 63 S E Performance commanding a £22,530 premium over the GT 63 S, it's expected to rise considerably over the old S63 4Matic.