AMG pumps new flagship PHEV S-Class to 791bhp

Plug-in hybrid Mercedes-AMG S63 is the most powerful S-Class yet and has 1054lb ft

The Mercedes-AMG S63 has been reborn as a plug-in hybrid performance saloon housing an electrically assisted 4.0-litre V8 that develops up to 791bhp. Set for UK sale early next year, the luxury super-saloon runs an updated version of the twin-turbocharged engine used by its predecessor, but now adopts a rear-axle-mounted electric motor and a 13.1kWh lithium ion battery. The set-up is similar to that of the Mercedes-AMG performance car division's recently introduced GT 63 SE Performance.

The new petrol-electric drivetrain brings an additional 214bhp over the old S63, which makes the 2023 model - officially called the S63 E Performance - the most powerful series-production S-Class model to date. Even more impressive is the increase in torque: up by 391lb ft to 1054lb ft.

This means the new S63's reserves eclipse those of even the previous-generation S65, whose twin-turbocharged 6.0-litre V12 petrol engine delivered 624bhp and 737lb ft.

However, the added muscle is not without a substantial weight penalty. The car arrives with a claimed kerb weight of 2595kg (525kg more than its predecessor), albeit with what Mercedes-AMG's head of technical development, Jochen Hermann, describes as "optimised weight distribution".