Background
We get it: you're sceptical. We were too. How can a 2.0-litre four-cylinder engine credibly replace a 4.0-litre V8 and make this generation of Mercedes C 63 worthy of succession in this classic model line? There are other questions too. What's the point in it now being Plug-in Hybrid? Particularly as it can only go 8 miles in EV mode. Why are there now no coupes and convertible versions? And is this the beginning of the end of Mercedes' AMG sub-brand as we know it?
We'll start with the last question first. The answer is no. AMG is merely reinventing itself. For the time being, V8s will continue in larger models, but smaller ones will get electrified combustion powerplants like that of this C 63 which make up for lower capacity with an all-electric boost. And alongside all of this, a new AMG.ea platform will allow the development of the range of full-battery performance EVs that AMG will need for the future. That's enough for now. We'll answer the other questions as we go along.
Driving Experience
How can a C 63 have a four cylinder engine? And be reborn as a Plug-in Hybrid? It all seems contradictory to the kind of car this was and hopefully still is. Well for a start, this isn't just any four-pot PHEV powertrain. It has a track record from use in non-EV form in the market's fastest hot hatch, the AMG A 45. And as a result of fiendish technical complexity, it develops more power than the old C 63's 4.0-litre V8, with a 680hp combined output.
There are other upgrades too. 4WD for instance - something the C 63 has always lacked and the continuing lack of which would have put it on the back foot against current BMW M3 and Audi RS 4 rivals. There's also now a full-electric drive-off setting allowing you to leave the house early in the morning without waking everyone up and annoying the neighbours.
By and large though, you choose a C 63 because you want to hear what the engine can do. And AMG promises that in 'RACE' mode, the most fiery of the eight main drive settings, you really will, particularly if you engage 'RACE START' and fire the car off the line to reach 62mph in just 3.4s. That's if you're quick with the paddle shifters for the 9-speed auto gearbox. Top speed is 174mph.
More on that drivetrain now. Even without the assistance of electric motor, the 469hp 2.0-litre engine is the world's most powerful four cylinder unit. Add in the rear axle-mounted 204hp electric motor (which has its own 2-speed gearbox) and total system output rises to class-leading levels, the 680hp figure we mentioned earlier backed by a thumping 1,020Nm of torque.
Design and Build
As with the previous C 63, there's a choice of saloon and estate body styles. Unlike with that model, there are no coupe or cabriolet options. Those will be covered off by fast versions of the new Mercedes CLE.
Visually, as you'd want, the C 63 has far more pavement presence than an ordinary C-Class. The need for extra cooling hardware pushes out the front bumper, increasing body length by 50mm. The bonnet with its air outlets is also unique. As is the front valance with its AMG grille and shutters that open or close depending on the engine's need for cooling air. The wheel arches are 76mm wider too, housing 19 or 20-inch alloy rims.
As with the standard C-Class, the cabin is a radical generation on with this model, thanks primarily to the huge MBUX centre screen, which here gains various bespoke AMG and Hybrid-specific displays. The instrument screen is bespoke too, gaining a 'Supersport' display style which uses a vertical menu structure. Even the Head-up display has AMG-specific 'Race' and 'Supersport' formats. Away from screens, you grasp a twin-spoke AMG Performance steering wheel. And there are AMG sports seats which many owners will want to upgrade to the more prominently-bolstered AMG Performance seats.
Space in the rear is slightly improved by this generation model's 25mm wheelbase length increase: it's still comfortable for two but a squash for three. Out back, the 455-litre boot capacity is competitive in the saloon but if you prioritise that, you'll want the Estate variant. Its automatic tailgate rises to reveal 490-litres of luggage room, 30-litres more than before. With the seats folded, that rises to 1,510-litres.
Market and Model
This C 63 S E PERFORMANCE model has been pitched well above an equivalent BMW M3 Competition saloon with xDrive. One of those costs around £81,000, but the asking figure for this Mercedes is around £98,000 for the saloon, with another £1,600 or so for the alternative estate version. That gets you the only trim option offered - fully-kitted-out 'Night Edition Premium Plus'.
There are some key options that owners will want to look at - like the upgrade from 19 to 20-inch wheels, the latter with a really smart forged design. Numerous paint finishes and equipment items are also available to provide further individualisation. The AMG matt paint finish 'graphite grey magno' is available exclusively for the C 63 S. The exterior design can be further accentuated with the 'AMG Exterior Carbon Fibre packages I and II', the 'AMG Night packages I and II' or the 'AMG Aerodynamics Package'.
There are also many individual choices available for the interior. Exclusive colours and various nappa leather upholsteries with an embossed AMG emblem in the front head restraints serve to emphasise either the sporty or the luxurious side of the C 63 S. You're going to want to look at the upgrade from sports to 'AMG Performance' seats. The special feature with those is the seat side bolsters with weight-saving openings that also allow better ventilation. If nappa leather upholstery is selected, these also feature a contrasting colour as an extra highlight. The shape of the backrest tapers towards the bottom and the AMG logo is positioned between the matt chrome openings below the integrated head restraint.
Cost of Ownership
Obviously, the whole point of switching to a Plug-in Hybrid powertrain here is to gain extra efficiency and (you'd think) some EV range thrown in too for your commuting journeys, so you don't have to use the powerful petrol engine until you get to roads where you can really enjoy it. So how does Mercedes explain the fact that this PHEV model offers only 8 miles of range? It's somewhat disappointing given that an ordinary Plug-in Hybrid C-Class like the C300e manages a segment-leading 68 miles of EV range.... But to make observations like this is to miss the point of this powertrain. It's made for performance not EV range. Mercedes says that it's not even essential that C 63 owners plug their cars in.
The idea behind use of an electric drivetrain here is based around providing the instant power that the petrol engine can't. And generating efficiency as you drive, so even if the 6.1kWh lithium-ion battery doesn't have a lot of charge, you'll still be getting a benefit. The C 63's Hybrid system can regenerate over 100kW of electric power under braking to feed back to the battery; Mercedes claims that in 30 minutes of driving, you can completely discharge the battery and recharge it twice. All of which is just as well because this PHEV powertrain is heavy, tipping the scales at 2,111kg. To give you some perspective, the BMW M3 xDrive weighs 1,780kg. The driver can select four different regeneration levels using the right hand AMG steering wheel button. Combined cycle fuel economy is quoted at 26.9mpg (about 5mpg worse than the mild hybrid C 43) and CO2 emissions are rated at 156g/km (46g/km better than a C 43). To give you some perspective on that, the old V8 C 63 model was quoted at 34.5mpg and 192g/km in saloon form at launch - but owners will tell you that those were fantasy figures. This one should get much closer to the quoted official stats.