Test Drive: Five minutes with a Mercedes-AMG C 63 S Cabriolet

What is it?

The most glamorous version of Mercedes-AMG’s performance hero, the C 63. You can have the C 63 in two power outputs, of either 476- or 510hp (the latter of which leads to ‘S’ badging), and then in four bodystyles: Saloon, Estate, Coupe and Cabriolet.

That leads to an eight-strong C 63 family, which is unprecedented in AMG’s history of making go-faster Mercs, and at the top of this expanded tree is the C 63 S Cabriolet, which is what we’re driving here. It’s the most expensive of all eight C 63s in unadorned format, so we need to know whether the Cabriolet is worth its considerable premium.

Why are you driving it?

While the exotic appeal of an open-top car with a 510hp twin-turbocharged V8 engine cannot be underestimated, in actual fact it just so happens that convertibles are never as good to drive as their siblings with fixed metal roofs. This is a simple structural consideration: the roof is an inherent part of a car’s rigidity, so getting rid of it for a fancy folding feature means the vehicle becomes less stiff as a result.

Manufacturers try to get around this drawback by including structural bracing down the sides of the convertible to compensate, but this only adds weight – so what you have is a heavier and looser car, which makes for less pleasing driving characteristics. And this relative lack of torsional rigidity is only exacerbated when carmakers put a huge engine into a convertible and then give it the sort of sporting aspirations that are brought about by the use of the letters ‘AMG’.

But can the C 63 S possibly navigate its way through these potential pitfalls and provide a truly thrilling steer?

What do you like about it?

Any V8 AMG is characterised by incredible noise and the C 63 S Cabriolet is no exception. One benefit to having a roof you can drop – which, on the Mercedes, is fully electrically operated, taking 20 seconds to raise or lower, a process you can even do on the move if the car is travelling at less than 31mph – is that you can better hear both the exertions of the motor and the noisy exhausts.

And the C 63 S is happy to oblige on both scores, providing one of the truly great modern motoring soundtracks. The engine gargles with menace at low revs and roars with searing intent near the redline, while – in the car’s Sport+ and Race modes – the exhausts pop, bang and burble in a joyous riot of sound. For the utterly tremendous noises it makes alone, the C 63 S is well worth the entry fee.

Luckily, though, it is extremely well-sorted in the dynamics department. The engine and gearbox work beautifully in tandem to provide absolutely monster performance in all situations, but it’s the wonderfully weighty and feelsome steering that is the star. Electrically assisted power steering systems tend to be numb in extremis, yet one of the companies that seems to have got the best grasp on these set-ups is AMG; aided here by the decision to have smaller 19-inch wheels on the front axle (part of a forged alloy package costing £1,735 on this car).

There’s plenty of information coming back to you about what the front tyres are doing at any given point, although we can tell you now that they are typically hanging on with almost preternatural tenacity. For all its overall mass and the fact it has a big V8 stuffed into its nose, the C 63 S Cabriolet resists understeer admirably.

Furthermore, the C 63’s adaptive dampers provide a great blend between ride comfort and body control in all of their drive settings, while the brakes cope well with the Cabriolet’s near-two-tonne kerb weight. It therefore drives in a magnificent fashion, whether you’re out having a sunny Sunday blast with the roof down, or you’re simply cruising along with the hood up and getting from A to B.

This is to say nothing of the AMG’s extraordinarily muscular looks, which we heartily approve of, nor its fantastic interior. You’ll want the £1,295 Premium Package, by the way, which adds a Nappa leather-look dashboard and door cards with contrast stitching, the LED Intelligent Light System and a stonking Burmester 13-speaker surround sound system with a nine-channel amp, rated at 590 watts; but don’t worry, if you don’t want to splash out extra cash then the C 63 S is pretty well specified as standard for your outlay of almost £73,000. As it should be.

In essence, while it might not be quite the sharpest AMG you’ll ever drive, the C 63 S Cabriolet is nevertheless a superb performance car that brilliantly stimulates its driver’s senses, with the added benefit of being able to provide top-down motoring on the sunnier days we get in this country. Marvellous.

Any issues?

The C 63 S has a lot of torque going to the rear axle only, so even in dry conditions the throttle needs to be treated with respect. Start flooring the accelerator in lower gears and the back of the Mercedes will twitch as the mighty 20-inch rear tyres struggle to keep their grip on the tarmac.

It’s by no means rampantly wayward and unruly, but it is one of those cars where you start to wonder if the company’s 4Matic all-wheel drive might have helped matters; indeed, Stuttgart and Affalterbach have decided between them that fitting 4Matic as standard to the C 63’s unhinged bigger brother, the E 63 S (with 612hp!), is absolutely essential.

Of course, 4WD adds even more weight, so that might not help the C 63 S Cabriolet’s cause, because – even though it is magnificent by the standards of open-top performance cars – we’d still prefer our V8 C-Class to have a fixed roof.

The less-expensive Coupe is an even more involving drive than the Cabriolet, but the coolest choice is surely the C 63 S Estate, truly the car that can do practically everything you would ever need of one vehicle.

What’s it like as a business vehicle – are there any tax benefits?

Sadly, 4.0-litre V8 convertibles don’t tend to be built to satisfy company car fleet requirements. The Mercedes’ 200g/km+ CO2 emissions mean punitive first year’s VED of £1,200 and then its £72,740 basic list price ensures it also falls into the £450 per annum bracket of any car priced at more than £40,000; that’s to say nothing of the 37% Benefit-in-Kind rate.

However, if you’re a successful business owner and you want something a little bit extravagant in which to transport your significant other and children at the weekends, the C 63 S is a great option, because while its Mercedes badge is undeniably desirable, it’s the sort of understated performance car you can park in places where you’d never dare leave a Ferrari, Porsche, McLaren or similar.

Where does it rank in class right now?

If you want a blisteringly quick, premium convertible that provides an all-round driving experience of supreme privilege and excitement, then there’s little that can beat the Mercedes-AMG C 63 S Cabriolet for anything like this money.

It’s certainly way ahead of the BMW M4 Convertible, even if the Munich car is fitted with the Competition Package, and we have no doubts the Mercedes will see off the impending 450hp Audi RS 5 soft-top as well. In truth, you’re going to have to be looking at something like an Aston Martin or Bentley convertible to make the C 63 S feel ordinary, and that type of car costs well in excess of £100,000.

Yes, there are better drivers’ machines in the C 63 family – not least the Coupe model – and the S Cabriolet is by no means cheap when it starts knocking on the door of £80,000 for our C 63 as tested, but then unremitting automotive prowess like this Mercedes-AMG is rarely inexpensive. It’s an absolutely cracking car.

TECH SPEC

  • Model: Mercedes-AMG C 63 S Cabriolet
  • Price: C-Class Cabriolet range starts from £36,945; C 63 S Cabriolet from £72,740, car as tested £76,665
  • Drivetrain: 4.0-litre twin-turbocharged V8 petrol, seven-speed AMG Speedshift MCT automatic transmission, rear-wheel drive
  • Economy: 31.7mpg
  • CO2 emissions: 208g/km – £1,200 VED first 12 months, then £450 per annum next five years, then £140 annually thereafter; 37% benefit in kind
  • Top speed: 155mph (limited)
  • 0-62mph: 4.1 seconds
  • Power: 510hp at 5,500- to 6,250rpm
  • Torque: 700Nm at 1,750- to 4,500rpm