The hottest Mercedes-Benz C-Class is taking shape.

    The plug-in hybrid Mercedes-AMG C63 has been snapped during testing, revealing its tough-looking body.

    There isn’t too much surprising about the way it looks. Despite the camouflage, we can see the car has the trademark Mercedes-AMG grille and an aggressive air intake down low.

    It rides on massive blacked-out alloy wheels, behind which sit oversized brakes. The calipers aren’t bronze, which means we don’t know if they’re carbon ceramics or not, but suffice to say the C63 won’t be light on for stopping power.

    Down back, there are four squared-off exhaust pipes and a pronounced diffuser, which stick out in contrast with the rounded, smooth shape of the new C-Class.

    Merceds-AMG has confirmed it’s re-engineered the A45 AMG’s M139 2.0-litre turbocharged four-cylinder engine for longitudinal applications and will use it in the AMG C-Class range.

    It’s been reworked and pumps out more power than before.

    From a base of 330kW of power, the fettled M139 engine can be combined with an electric motor developing up to 150kW and 320Nm of torque, though combined power and torque figures have yet to be released.

    The A45 currently produces 310kW of power and 500Nm of torque, while the current C63 S produces 375kW of power and 700Nm of torque.

    Mercedes-AMG says the total power and torque from this new electrified powertrain will surpass current “comparable” models with non-hybrid V8 engines.

    As in the upcoming V8-powered Mercedes-AMG GT73e 4-Door Coupe, the electrified C-Class will mate an internal combustion engine with an electric motor, a high-performance battery, and the AMG Performance 4MATIC+ all-wheel drive system.

    Mercedes-AMG calls this drivetrain E Performance, and depending on the combustion engine used the drivetrain can produce upwards of 600kW of power and 1000Nm of torque with a 0-100km/h time of less than 3.0 seconds.

    In E Performance cars, the electric motor is positioned on the rear axle and is integrated with an electrically-shifted two-speed transmission and the electronic rear axle differential lock.

    The lightweight battery is also located above the rear axle.

    Instead of sending power through the nine-speed automatic transmission, the electric motor acts directly on the rear axle. The differential lock can in turn allocate the optimum torque to each rear wheel.

    If slip on the rear axle increases, power from the electric motor can be transferred to the front wheels for a short time to increase traction.

    The two-speed transmission’s electric actuator switches it to second gear at around 140km/h at the latest.

    The 6.1kWh battery, which weighs 89kg, is said to use Formula 1 technology and has fast energy absorption and high power density of 1.7kW/kg.

    The 400V battery features 560 cells, each cooled individually and permanently surrounded by a coolant based on an electrically non-conductive liquid.

    With the battery kept at a consistent temperature window of 45 degrees Celsius, the battery can retain its high performance capacity even during aggressive track driving.

    Drivers can select between six drive modes: Electric, Comfort, Sport, Sport+, Race and Individual.

    In Electric mode, the car can be driven purely as an EV at speeds of up to 130km/h and defaults to rear-wheel drive.

    However, if the rear wheels lose traction, power from the electric motor is transmitted to the front wheels.

    In Race mode, the car will take off using both combustion engine and electric motor power and the electric motor will continue to support the engine during hard acceleration.

    There are also four AMG Dynamics modes, which alter the ESP settings, the all-wheel drive system, and the rear differential lock.

    Basic is assigned to the Comfort and Electric drive modes, while Advanced is paired with Sport, Pro is paired with Sport+, and Master is coupled with Race.

    The latter leans towards oversteer and can only be activated if you switch the ESP to Sport Handling Mode or switch it off entirely, and is therefore intended for track use only.

    As Mercedes-AMG has previously announced, it’s developed an electric exhaust-gas turbocharger which uses Formula 1 technology and will also be used in the Mercedes-AMG Project One hypercar.

    It uses a small electric motor integrated between the turbine wheel on the exhaust side and the compressor wheel on the air intake side, driving the compressor wheel before exhaust gas flow enters.

    When engaged, the turbocharger achieves speeds of up to 156,000rpm, and can maintain boost pressure at all times – even when the driver takes their foot off the accelerator or applies the brakes.

    Additionally, there are four levels of recuperation with the highest level affording one-pedal driving, plus a belt-driven, 10kW starter-alternator to keep auxiliary units such as the air-conditioning running when you’re at a traffic light.

    Between the regular C-Class and the hi-po C63, the upcoming C43/C53 is also expected to move to an electrified four-cylinder powertrain.

    That means the entire C-Class range, from the tamest C180 to the spiciest AMG variant, will use four-cylinder engines for the first time.

    MORE: Mercedes-AMG C news and reviews

    Scott Collie

    Scott Collie is an automotive journalist based in Melbourne, Australia. Scott studied journalism at RMIT University and, after a lifelong obsession with everything automotive, started covering the car industry shortly afterwards. He has a passion for travel, and is an avid Melbourne Demons supporter.

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