After all, it will not adopt the nomenclature “73”. AMG's new “monster”, its first plug-in hybrid, will be called GT 63 S E Performance and to live up to the title of super-summary of the range, it is accompanied by numbers… absurd.
In total it delivers 843 hp (620 kW) and a torque that varies between a “fat” 1010 Nm and a “crazy” 1470 Nm that are capable of catapulting this substantial saloon up to 100 km/h in just 2.9s and even at 200 km/h in less than 10s. Maximum speed? 316 km/h. Performance “Monster”? There doesn't seem to be much doubt.
In essence, the GT 63 SE Performance marries the GT 63 S we already knew and tested — twin-turbo V8 (639 hp and 900 Nm), nine-speed automatic and four-wheel drive — with an electrified rear axle, which allows for achieve these unprecedented numbers in a production AMG — the AMG One will surpass them, but it's a machine of its own.
Rear axle "electrifying"
The rear axle is now equipped with an EDU (Electric Drive Unit or Electric Propulsion Unit) that combines a synchronous electric motor with a maximum power of 150 kW (204 hp) and 320 Nm of maximum torque, with an electronically controlled self-locking differential and a two-speed gearbox with electric actuators.
This “engages” the second gear, at the latest, at 140 km/h, coinciding with the moment when the electric motor reaches its maximum rotation: 13 500 rpm.
This mechanical configuration — a combustion engine positioned longitudinally at the front, coupled to a nine-speed automatic gearbox (AMG Speedshift MCT 9G) and a rear-mounted electric motor with a two-speed gearbox — differs from other hybrid proposals by separating the two power units.
This allows the electric motor to act directly on the rear axle, without having to go through the nine-speed automatic transmission that is mated to the front-mounted V8.
According to AMG, the response to our requests is even faster, boosting agility and also traction. However, if the rear axle starts to slip more than it should, some of the power from the electric motor can be sent forward via the driveshaft — efficiency above all else, but the GT 63 SE Performance still includes a “mode” drift".
Performance at the expense of autonomy
In addition to the rear axle being electrified, the battery needed for its operation is also there in the back, above the rear axle — AMG speaks of an optimized mass distribution, enhancing the dynamic capabilities of the sports saloon.
An AMG plugged in? Yes, get used to it.
Bearing in mind that the first plug-in hybrids capable of “biting” the 100 km of electric autonomy begin to appear, the “slim” 12 km announced for the Mercedes-AMG GT 63 S E Performance is surprising. Whoa… unlike the batteries of these new plug-in hybrids, with a capacity of 25-30 kWh, the E Performance has only 6.1 kWh of capacity.
The 400 V battery was designed to get maximum performance out of it as quickly as possible, not for “electric marathons”. On its own, it adds 89 kg to the vehicle's mass and is capable of delivering 70 kW (95 hp) continuously, reaching a peak of 150 kW (204 hp) for periods of 10 seconds. It thus achieves a power density that doubles that of other batteries: 1.7 kW/kg.
To achieve this performance, Mercedes-AMG innovated by directly cooling the 560 cells that make it up, a decisive factor in achieving the desired performance, longevity and safety. There are 14 liters of refrigerant that keeps each cell individually “fresh”, keeping them at an average temperature of 45°C, its optimal operating window.
The electrics of the GT 63 S E Performance also help justify the optimistic 8.6 l/100 km combined announced and the official CO2 emissions of just 196 g/km (WLTP).
Serial carbon ceramics
Mercedes-AMG has given us several specifications, but none for the mass of this portent — only referred to its optimized mass distribution. If the “normal” GT 63 S already loads 2120 kg, this GT 63 S E Performance should comfortably exceed that value.
Wheels can be 20" or 21" and behind them are generous carbon-ceramic brake discs.
Perhaps it's not surprising to learn that in order to quickly “cut” the moment at such massive mass, Affalterbach's officials decided to equip their new “performance weapon” with carbon-ceramic disc brakes. Bronze fixed calipers have six pistons at the front and a floating caliper at the rear of a single piston. These bite into huge discs — which hide behind 20″ or 21″ wheels — 420mm x 40mm at the front and 380mm x 32mm at the rear.
What's more, the electric machine adds regenerative braking to the GT 63 S E Performance with four levels controlled by buttons on the steering wheel — starting at “0” or without regeneration, up to the maximum level “3”.
Also to keep things under control, the Mercedes-AMG GT 63 S E Performance comes standard with the AMG RIDE CONTROL+, which consists of a self-leveling, multi-chamber air suspension that is combined with electronically adjustable damping.
It is complemented by the AMG DYNAMICS which determines how the vehicle must react, influencing the control strategies of the ESP, the four-wheel drive system (4MATIC+) and the self-locking rear differential. There are several programs available — Basic, Advanced, Pro and Master — which are available depending on the driving modes (AMG DYNAMIC SELECT) selected — Electric, Comfort, Sport, Sport+, RACE, Slippery and Individual.
