Mercedes-AMG will make PHEV debut with 800bhp-plus GT73e

Additionally, this means the electric motor’s torque is not capped by the limitations of the gearbox. It also provides the basis for improved front-to-rear weight distribution and allows significantly more efficient energy recuperation as there are no mechanical losses from the gearbox. Kinetic electricity harvested during braking and periods of trailing throttle is fed straight back into the battery.

AMG sources have revealed to Autocar that the GT73e’s electric motor will have up to 201bhp and 268lb ft. Reports suggest it shares key parts with the ZF-produced ‘M0’ asynchronous electric motor used in the pure-electric Mercedes-Benz EQC and EQV.

The motor’s reserves are combined with the GT73e’s petrol engine, which in its GT63 S 4-Door Coupé tune kicks out 639bhp and 664lb ft, to deliver what Autocar has been told are “previously unattained levels of power and torque” for a road-going four-door AMG model.

The new four-door will “at least match” the 805bhp promised by AMG when it first revealed plans for a petrol-electric drivetrain with the unveiling of the GT concept in 2017. This would provide the GT73e with over 130bhp more than its hybridised Panamera rival, which packs a combined 671bhp from its electrified V8.

Total torque output should be impressive, too, extending to somewhere in the region of 740lb ft. The high overall torque load is made possible because the torque from the electric motor is not restricted by the gearbox and four-wheel drive system. Instead, it is fed directly to the rear wheels.

The four-wheel-drive GT73e won’t be AMG’s most powerful road-going model, though. That honour goes to the delayed One hypercar, which is motivated by a Formula 1-derived electrified V6 with over 1000bhp and 1000lb ft.

Electrical energy for the P3’s rear-mounted motor is supplied by a liquid-cooled lithium ion battery pack under the floor of the GT73e’s boot. Its capacity and chemical process remain under wraps less than six months before the new model’s planned unveiling, but insiders suggest it will use the same cells as the newly unveiled plug-in hybrid version of the fifth-generation C-Class.

Despite a substantial increase in kerb weight from the use of an electric motor and battery, the GT73e promises to crack 0-62mph in under 3.0sec, undercutting the GT63’s claimed 3.2sec sprint time.

The added performance will be combined with an ability to run on electric power only. Exact figures have not yet been made official, but recent plug-in hybrid Mercedes models have offered ranges of up to 62 miles from batteries of between 25.4kWh and 31.2kWh in capacity, as well as DC charging compatibility.

The original Hammer

The Mercedes-Benz AMG 300CE Hammer made its debut at the 1987 Geneva motor show. Based on the 300CE, it swapped that model’s petrol straight six for the 5.6-litre V8 from the 560 SEL: the fabled M117. The original model offered 355bhp and 376lb ft.

However, the legend wasn’t complete until Mercedes-Benz began offering a second output option, which upsized the M117 to 6.0 litres, with power increasing to 385bhp. The engine modifications were overseen by Erhard Melcher – the ‘M’ in ‘AMG’, and one of the performance division’s original founders. Key changes included a new four-valve cylinder head (in place of the standard two-valve set-up), reworked camshafts and lighter pistons.

The 300CE Hammer was renowned more for its segment-leading torque output than outright power, and at 417lb ft it was prodigious for performance cars of the time, helping to provide the model with a 0-62mph time of 4.8sec and 190mph top speed.