This is it, the all-new Mercedes-AMG C63 S E Performance. Based on the current W206 Mercedes-Benz C-Class and introduced in the year AMG celebrates its 55th birthday, the latest C63 marks a radical departure from a familiar formula and will continue to be offered in sedan and wagon forms.

As a start, the new C63 S does not come with a V8 engine like its predecessors. Instead, the sports sedan features the M139l (l for longitudinal installation) that is also used by the C43 and SL43, albeit further developed to make it the most powerful series-production four-cylinder engine in the world.

Yes, it’s just four cylinders and there’s only 2.0 litres of displacement, but the C63 S’ M139l churns out a mighty 476 PS (469 hp or 350 kW) at 6,725 rpm and 545 Nm of torque from 5,250 to 5,500 rpm. That’s more than the other M139l-equipped cars and even the A45 S, which is powered by the transverse-mounted M139.

To achieve those figures, the carmaker drew upon its Formula 1 know-how and incorporated an electric exhaust gas turbocharger, where an electric motor around four cm thin is integrated directly on the turbocharger shaft between the turbine wheel on the exhaust side and the compressor wheel on the intake side.

This spins the shaft to generate boost well before the exhaust gas flow takes over, which the company says improves response and allows higher torque to be accessed at low revs. In the C43 and SL43, the electric turbo operates on a 48-volt mild hybrid system, but the C63 S kicks things up a notch with 400-volt system. Additionally, there’s also a larger turbocharger, which enables a higher airflow rate for more power, although the engine’s compression ratio is reduced from 10:1 to 9:1 to accept the additional boost.

Another aspect of the engine is a belt-driven starter generator (RSG) that combines an alternator and starter in one component. Operating on the same 400-volt architecture, the RSG serves to start the engine and power A belt-driven starter generator (RSG) combines an alternator and starter in one component. ancillary components such as air-conditioning or driving lights.

The engine sends drive to all four wheels via an AMG Performance 4Matic+ fully variable all-wheel drive system and a nine-speed automatic gearbox with a wet multi-plate clutch – replaces the torque converter – that is marketed as the AMG Speedshift MCT 9G.

As a result, this is the first time the C63 gets all-wheel drive, which is something rivals like the BMW M3 and Audi RS4 Avant are already offering. Like its larger sibling, the E63, there’s a Drift mode that decouples the front axle to make atomising tyres a lot easier.

For even more performance, the C63 S also gets an electric drive unit (EDU) to form what the company calls a P3 hybrid layout. The EDU features an electric motor positioned at the rear axle that is rated at 204 PS (201 hp or 150 kW) and 320 Nm and integrated with a two-speed gearbox (the second gear comes into play beyond 138 km/h) as well as an electronically controlled rear axle differential lock.

With the C63 S’ M139l and EDU, the total system output is a monstrous 680 PS (671 hp or 500 kW) and 1,020 Nm. That’s more than the previous, W205-based C63 S that manages just 510 PS (500 hp or 380 kW) and 700 Nm from its “antique” 4.0 litre twin-turbo V8. It should also be noted that there won’t be a non-S C63 base variant for this generation.

With all that power on tap, the C63 S in both body styles takes just 3.4 seconds to get from 0-100 km/h – 0.6 seconds faster than the previous C63 S. The top speed is capped at 250 km/h, but this can be raised to 280 km/h (sedan) or 270 km/h (wagon) with the optional AMG Driver’s Package.

Turning our attention back to the EDU, the system is similar to the one used in the V8-powered GT63 S E Performance, and we’ve already been introduced to it when the company detailed its E Performance strategy last year. In operation, the electric motor acts directly on the rear axle to add to the propulsion power, with all 204 PS available to provide a temporary boost for up to 10 seconds.

However, in the event there’s slip detected at the rear, the electric motor can also send power to the other end via a mechanical connection to the all-wheel drive system through a cardan shaft and the drive shafts of the front wheels. This also means all-wheel drive is always available, even if the engine is not running.

Don’t expect much in the way of electric-only range though, as the C63 S only has a lithium-ion battery with an energy capacity of 6.1 kWh that is good for just 13 km. Weighing in at 89 kg, the battery can deliver a continuous output of 70 kW and 150 kW, the latter for 10 seconds as mentioned earlier.

Made up of 560 cells that are individually cooled, the whole module is linked to the engine’s cooling system to maintain an optimum operating temperature window averaging 45 degrees Celsius for consistent performance when charging or discharging energy. The AMG high-performance battery (HPB), along with the electric control unit, is stacked on top of the electric motor and transmission to form a compact unit that tips the scales at 250 kg.

Users can charge the battery via the 3.7-kW onboard AC charger, but the company has made it clear that performance, not efficiency, is the primary purpose of the EDU. There are four regeneration modes to keep the battery fed on the move, with Level 3 allowing for more than 100 kW of energy to be recuperated.

Meanwhile, there are twice the number of modes in the AMG Dynamic Select system: Electric, Comfort, Battery Hold, Sport, Sport+, Race, Slippery and Individual. The first is self-explanatory, allowing for all-electric driving at speeds of up to 125 km/h, while Battery Hold keeps the battery state of charge at a constant.

Sport and Sport+ varies the interaction of the engine and electric motor, with the latter providing up to 80% electric boost. In Race mode, the system ensures that the battery capacity never drops below 30% so 100% of electric boost is available. Slippery mode dulls things down to make things more manageable, while Individual is for personalised settings.

Moving beyond the technically impressive drivetrain, the C63 S is equipped as standard with AMG Ride Control steel-spring suspension with Adaptive Damping System, the latter featuring remote-reservoir dampers with a solid piston and electrohydraulic external valves.

There’s also three-stage variable steering that increases or decreases steering power assistance based on the selected drive mode. Rear axle steering is also standard, enabling the rear wheels to steer at an angle of up to 2.5 degrees at speeds of up to 100 km/h. Beyond that speed point, the angle is reduced to a maximum possible of 0.7 degrees.

AMG Dynamics is also part of the standard specification, allowing drivers to adjust how much the Electronic Stability Programme (ESP) intervenes based on the chosen drive mode at the time, with Master allowing for maximum agility if you know what you’re doing. The carmaker also throws in a system that records the actual sound of the combustion engine via a pressure sensor in the exhaust system, “enriching” it and piping it into the cabin for a more emotional experience.

To slow down the C63 S, the car gets the AMG high-performance composite brake system made up of six-piston fixed calipers at the front and one-piston floating calipers at the rear – the company also a carbon-ceramic system as an option. Powerful brakes are necessary as the C63 S, even with its downsized engine and relatively lightweight EDU, has a kerb weight of 2,111 kg (2,145 kg for the wagon), which is about 300 kg more than its V8-powered predecessor.

As for the looks, it’s the W206 that we’re all familiar with, but with AMG-specific touches to amp up the visual presence. The front end is 50 mm longer and the front wings are wider, while the bonnet gets a slim air outlet in between the power bulges. A black AMG emblem is also used for the first time on a Mercedes-AMG model, replacing the Mercedes-Benz star with a laurel wreath on the bonnet.

The bumper is also unique to the C63 S, featuring large inlets, flics and air curtains to channel air to specific areas. Behind the Panamericana radiator grille are two electronically controlled Air Panels to regulate air flow into the engine bay.

Side skirts are also part of the exterior design, with the rear apron receiving a prominent diffuser and trapezoidal-shaped exhaust outlets. Also standing out are the large boot lid spoiler (the wagon gets a roof spoiler) and E Performance badge on the fenders beneath the side scuttles. The company offers 19-inch wheels as standard, but these can be upgraded to 20-inch units, and there are numerous paint finishes and other personalisation options available.

Inside, AMG sports seats are standard and can be replaced with the second-generation AMG Performance seats, with Nappa leather upholstery and contrasting accents. There’s also the AMG Performance steering wheel and AMG-specific displays for the Mercedes-Benz User Experience (MBUX) infotainment system that continues to feature dual displays.

With all said and done, what do you think of the new C63 S E Performance? Does its complex and highly electrified powertrain make up for the lack of a V8? Let us know your thoughts in the comments below.