Mercedes Benz C63 AMG

I have never really come to terms with super-fast Mercedes saloons. The four-door models that carry the three-pointed star have seemed a bit too solid and serious to be contenders among the road-racers epitomised by the BMW M3 and M5.

But when I encountered the new Mercedes C-class a few months ago I was bound to agree that the Stuttgart marque had changed direction and given its smallest saloon a sporty demeanour. It is, I suggested, the closest that Mercedes has come to making a 3-series.

Lurking in background was the version intended to drive home that idea. BMW’s new M3 had a 4-litre 415bhp V8 engine and Audi had anticipated that with a 4.2-litre 420bhp V8 RS4. Mercedes made it known that the AMG version of new C-class would have a 6.2-litre V8 developing 457bhp.

Years ago, before AMG became part of Daimler, its fastest and most powerful tuned Mercedes was a development of the S-class that it called the Hammer. That would be an appropriate name for the Mercedes C63 AMG; it delivers a killer blow to its two German rivals.

AMG, based in Affalterbach, Germany, is Mercedes’ equivalent of BMW’s M-Division. Although it is best known to the public for peripheral things like special wheels, steering wheels, seats and spoilers, the heart of AMG’s business is engines. It used to enlarge and otherwise modify standard Mercedes motors but now it has a V8 of its own, unrelated to those of the regular product line. Each AMG V8 is hand-built at Affalterbach by one technician whose signature appears on the engine plate.

That engine is the essence of the C63 but what advertises this as the fastest C-class is all the add-on stuff outside – the twin power domes on the bonnet, the swollen wheel arches, protruding sills and stretched-out air intakes. AMG insists that all this is necessary to maintain stability and keep the engine fed and cool but you have to wonder if it needs to be quite so ostentatious. There used to be something deliciously discreet about having a mighty motor in a standard-looking saloon but nowadays Mercedes knows that if you have it, you have to flaunt it.

AMG has done a more comprehensive job on the C63 than its previous versions of the C-class. Transmission, steering, suspension, brakes, wheels and tyres, even the action of the ESP electronic stability control, have been specially tuned.

All this shows as soon as you take to the highway. This is a truly fast car: 0-100kmph in 4.5 seconds, maximum speed limited to 250kmph (but capable to 280 if you pay extra for the Driver’s Pack and eliminate the limiter). The engine is a joy. It feels – and sounds – hard and strong and has a seamless power delivery. Whereas the M3’s V8 has the character of a racing engine and revs to 8,400rpm, the 6.2-litre AMG engine delivers its maximum power at 6,800rpm and provides 80 per cent of its 600NM torque from 2,000rpm.

There is no manual gearbox for the C63, only a version of Mercedes seven-speed automatic that AMG calls Speedshift Plus 7G-Tronic. This has fingertip paddles behind the steering wheel and a choice of three programmes: comfort auto, sport auto, and manual. For the first time in an AMG model, the electronics blip the throttle when changing down which not only sounds good and flatters the driver but also cushions the impact on the drive-line from an aggressive down-shift.

The steering is excellent, with just the right gearing and weighting, the brakes immensely powerful, and on a smooth, dry road, cornering grip is remarkable. Trouble is that, outside Germany, roads are rarely race-track smooth and the C63 is much less impressive on the broken and patched surfaces of UK by-ways. The ride is uncomfortably harsh and the reaction of the stiff suspension on country roads actually becomes a speed limiter; it can be a struggle to position the car as it crashes from bump to bump.

The ride is the only real flaw in this rocket-ship Mercedes and the optional 19-inch wheels (which most customers will specify) enhance the problem. The C63 is larger and heavier than the M3 and RS4 and feels it. Indeed, it seems even bigger from the low position of the special, close-fitting AMG seats. It is in any case a car that demands respect. Mercedes’ admirable safety provisions notwithstanding, a family saloon with a 6.2-litre V8 engine and 457bhp could spell plenty of trouble for the inexperienced or over-confident.

The big question is: Mercedes C63 AMG or BMW M3? It is not a direct comparison – and least not yet. The Mercedes comes only as four-door saloon with an estate version to follow. The BMW is a two-door coupe now but will soon also be available as a saloon.

The Mercedes wins for its effortless performance and more generous accommodation but the M3 would be my choice as a more finely-honed sporting car.

As you can tell, it’s a close-run thing.