Mercedes-AMG has taken the covers off the 2023 C 63 S E Performance, and the 680hp on tap from its 2.0-litre turbocharged four-cylinder hybrid-assisted powertrain takes some of the sting out of the loss of the sonorous 4.0-litre V8 engine that has powered all AMG 63 models since 2015.
The new engine, Mercedes says, is the most powerful four-cylinder unit in the world and the arrival of the C 63 S next year will add a new range-topper to the C-Class line-up with the most powerful production version of the saloon seen to date.
Initially launching in both saloon and estate variants, the C 63 S will employ some of the expertise Mercedes has acquired over the years from its racing programmes including an innovative new turbocharging system and a high-performance plug-in hybrid powertrain.
Under the bulging, vented bonnet lies that AMG four-cylinder engine churning out 476hp on its own and, when combined with the rear-mounted 204hp electric motor (supplied by a battery mounted over the rear axle for optimum weight distribution), the system can send a hefty 1,020Nm of torque to all four wheels through a complex all-wheel-drive arrangement of prop-shafts, a two-speed electric gearbox, nine-speed multi-clutch transmission and a rear limited-slip differential.
Acceleration ought to be sharp and relentless thanks to the application of some of those motorsport-derived technologies such as the electrically assisted turbocharger that uses a tiny electric motor to keep the wheel spinning and maintain turbo boost pressure at all times. In most turbocharged cars, the turbocharger unit relies on the exhaust gases to keep the turbine turning, which can result in a momentary delay between the driver putting their foot down and the engine responding, something that the Mercedes innovation aims to address.
As well as delivering plenty of power and torque to the rear wheels on its own, the electric motor helps to smooth out the overall power delivery under harsh acceleration. The motor's headline output figure of 204hp is, it should be noted, only available in short ten-second bursts; in everyday use, its continuous output is 95hp.
Although the C 63 S is technically a plug-in hybrid - there's an on-board 3.7kW AC charger to top-up the 6.1kWh directly-cooled battery - don't go expecting 50km of range; the best the C 63 S can do is 13km, which really isn't much, but Mercedes does admit that the purpose of the battery and motor is more to aid with the power delivery than to provide much in the way of electric-only driving.
That said, having the motor on hand can potentially help a driver out in a difficult situation; if the control systems detect slippage in one of the rear wheels, the motor can instantly send more power to the front wheels to increase traction, potentially getting the driver out of a skid or, given the C 63's performance bent, assisting them in getting around a corner faster.
Even if the way the C 63 S achieves its outright pace is of little interest, the result very much might be: thanks to that engine and the hybrid system, the AMG can hit 100km/h from a standstill in just 3.4 seconds.
New looks (sort of)
There's plenty more to the C 63 than just excessive power though. It looks different to and more purposeful than a standard C-Class certainly, but that's not surprising. It doesn't, however, look that much different to the lesser C 43 4Matic - not on first glance anyway. On closer inspection though, the C 63 is actually slightly bigger all round. The front wheel track is wider thanks to reworked suspension resulting in arches that are 76mm wider than that of a standard C-Class. The front has been lengthened by 50mm, too, and both the saloon and estate are 83mm longer than in their base forms. Even the wheelbase has grown by 10mm.
Inside sees standard sports seats or racier, more heavily bolstered alternatives. Behind the steering wheel is a large rectangular digital instrument cluster with a portrait-aspect infotainment touchscreen in the centre running the latest version of the Mercedes MBUX system.
The C 63 S can be driven in a range of self-explanatory driving modes, all selectable via the infotainment screen, and running the gamut from "Electric" to "Race" to "Slippery". Electric keeps the car in electric-only mode until the driver demands more power or the battery runs down; Slippery is, as the name suggests, designed for trickier conditions and surfaces, reducing the power and preventing the car from being driven in electric-only mode; Comfort strikes a balance of battery and engine power for everyday motoring; Sport and Sport+ tap into the car's performance potential a bit more, sharpening up the throttle response and gear shifts and turning up the boost from the motor a bit more; Race is more extreme than either Sport settings and is designed mainly for track use.
Also selectable is the level of damping, with the suspension using steel springs and adaptive dampers that allow drivers to choose between three different damping maps - Comfort, Sport and Sport+ - that change the firmness of the ride and thus how the car behaves on the road.
Stopping power in the C 63 is strong thanks to six-piston fixed brake calipers up front and floating one-piston calipers at the rear designed to resist fade under heavy use. As well as mechanical braking though, there are also four levels of regenerative braking ranging from nearly no regen to full one-pedal driving. That regenerative braking has been engineered to return as much energy as possible to the battery pack so that the driver always has the maximum amount of power available when they need it, such as when accelerating out of a corner or overtaking.
Although the performance of the new four-cylinder C 63 may surpass any V8-engined C 63 that has gone before it, there's the issue that a turbocharged four-cylinder engine will just never sound quite as evocative. That's something Mercedes has aimed to address with its exhaust system, which contains a pressure sensor that picks up the sound of engine and "enriches" it before piping it into the cabin through the speaker system making the sound of driving the C 63 more in keeping with the compelling performance.
Neither Irish pricing nor the arrival date for the Mercedes-AMG C 63 S E Performance have yet been announced.