Test Car Specifications
Model tested: Mercedes-AMG S 63 Cabriolet
Pricing: range from £110,120; S 63 from £135,675
Engine: 5.5-litre twin-turbocharged V8 petrol
Transmission: seven-speed Speedshift MCT gearbox, rear-wheel drive
Body style: two-door, four-seat cabriolet
CO2 emissions: 237g/km (VED Band L, £885 first 12 months, £500 annually thereafter)
Combined economy: 28mpg
Top speed: 155mph (limited)
0-62mph: 4.2 seconds
Power: 585hp at 5,500rpm
Torque: 900Nm at 2,250- to 3,750rpm
What's this?
The Mercedes-AMG S 63, one of two AMG models in the three-strong UK line-up of the new Mercedes S-Class Cabriolet, a variant revived by the marque after a 45-year hiatus. Given Mercedes already has the iconic SL two-seat luxury roadster in its ranks, and it could also, er... convertible-ise the AMG GT supercar, it would seem the German marque has an embarrassment of riches in terms of outrageously opulent open-tops, yet the S-Class's remit is to focus on unstinting comfort ahead of dynamic prowess. Which then makes the decision to turn 66 per cent of the range over to Affalterbach, an arm of the company whose sole purpose is to inject driving focus into a car, seem a little perverse; no matter, we're not complaining about a 585hp/900Nm four-seat cabriolet with the sort of posing power normally reserved for the likes of Ryan Reynolds.
AMG treatment enacts the same sort of changes on the S-Class Cabriolet as it does anywhere else in the wider Mercedes family. Specific design alloy wheels (19s on the 63, 20s on the 65) are complemented by a lower body kit that includes redesigned bumpers and side skirts, while at the rear are four exhausts embracing a vaned diffuser. If you're looking at the front, the A-wing air dam gives the game away most easily, but AMG specification hardly ruins the fantastic, balanced look of the Cabriolet. It also beefs up the interior with sports seats, an AMG-specific steering wheel, the performance brand's logo embossed on the centre armrest and some carbon fibre trim, and in terms of specific equipment upgrades, buying an S 63 adds Nappa leather, a Driving Assistance Package and a 13-speaker Burmester sound system to the already massively lengthy kit list of the S 500.
A quick note on that flagship, the S 65 Cabriolet. No doubt in this sort of marketplace, image is king and so Mercedes-AMG offering a goliath 630hp/1,000Nm V12 engine with all the trappings (you'd assume are necessary to satisfy bored, oil-rich tycoons) makes perfect sense, but for us it's the same dilemma as we grappled with driving the facelifted SL earlier this year. There's a ginormous £57,130 between the S 63 and the S 65 (it's £192,805!), and in terms of the on-paper stats there's nothing like as big a gulf between them on performance. Indeed, in most markets, the S 63 is empirically quicker than the S 65 (which we'll explain in the next section) and as we know that V12 is a muted operator, we'd definitely advocate the 5.5-litre V8 as the best AMG S-Class Cabriolet. More pertinently, the S 63 is 'only' £25,555 more than the S 500, so should you opt for comfort-over-speed or speed-over-comfort with this grandest of grand tourers?
How does it drive?
Ridiculously well, considering it tips the scales at 2,170kg. It feels no more unwieldy than the SL 63 and that's astonishing given there's a huge 325kg between the two of them. These high-end Mercedes convertibles obviously also pack the same drivetrain, which is the biturbo V8 engine mated to a seven-speed AMG Speedshift MCT transmission. The pace is ludicrous; the S 63 Cabriolet goes like a supercar, not a veritable land-yacht, and AMG further enhances the package compared to the S 500 by firming up the Airmatic suspension, sharpening the steering and fitting bigger, composite brakes. The net result is that the S 63 really can corner extraordinarily well for something five metres long and fitted with a soft-top - it'll put more of a grin on the keener driver's face than they would have been expecting.
Of course, hood down, the real benefit to be had here comes courtesy of the cacophonous soundtrack of the S 63. Mercedes-AMG currently has five engines sold under four badges: 2.0-litre, four-cylinder '45'; 3.0-litre V6 '43'; 4.0-litre V8 '63', and of course this 5.5, also a '63'; and then the 6.0-litre V12 '65'. All of them bar the four-cylinder are twin-turbos, while the four-pot has one giant blower fitted to it, and the widely accepted petrolhead knowledge is that forced induction ruins a car's voice. We would cite this 5.5, among all of these fantastically raucous AMG engines, as all the proof you need to denounce that knowledge as total baloney. There are few finer-sounding cars on sale today than the S 63 Cabriolet. It's not quite as loud as its SL 63 stablemate, mainly because the S-Class has a longer exhaust system and the front-seat occupants sit further from the tailpipes than they do in the two-seat roadster, but even so the noise of the S 63 Cabriolet is utterly marvellous. Enjoy downshifting for no good reason, just to make its quad exhausts spit furious bangs of unburnt fuel from their tips, shocking everyone in the vicinity. Enjoy its multi-tonal voice, which is grumbly at low revs, menacing in the mid-range and then creamy V8 bellowing goodness when closing in on the redline. Enjoy the decadence of a car that, on the pace, was showing something considerably in excess of 30 litres/100km consumption... That's, er, that's less than 9.4mpg. Crikey.
Thankfully, the AMG 63 does not fatally compromise the S-Class Cabriolet's magnificent ride, albeit it is ever so marginally less cosseting than the S 500. Regardless, it'll cruise along just fine when you're not driving it like a demented loon, the S 63 settling down into a loping gait backed up by discreet murmuring from the V8 when the throttle is only lightly open. The AMG steering is a total delight, even when driving slowly, as it's utterly linear and faithful to inputs with its responses. As an easy car to drive gently that turns into a roaring maniac when the mood takes you, the S 63 has few equals and, perhaps understandably, we adore it.
However... there's a secret to its other-worldly road-holding and it's to do with the old left-hand drive v right-hand drive debacle. Left-hand drive AMG 63s alone of all the S-Class Cabriolet variants benefit from 4Matic all-wheel drive; right-hand drive S 63s make do with power going to the rear axle alone. The 4Matic version is the S 63, which, as we mentioned earlier, is quicker than the S 65 flagship. Despite the weight penalty all-wheel drive incurs, the extra traction afforded off-the-line allows for a scarcely believable 3.9-second 0-62mph time, shaving three tenths from the rear-wheel drive 63's time and beating the rear-drive S 65's data of 4.2 seconds in the process. Anyway, as we've only driven a left-hand drive S 63 Cabriolet, we're going to have to make a supposition about how the UK cars will drive and it is based on our knowledge of the SL 63's character, a car that is only ever rear-wheel drive. So our assumption is this: the lack of drive to the front wheels might slightly alter the S 63's willingness to turn in, but it will not ruin the general chassis brilliance of this talented convertible GT.
Verdict
What makes the Mercedes-AMG S 63 Cabriolet a five-star car is the fact that its sporty pretensions are turned into genuine dynamic ability, all without spoiling the cultured character of the S-Class Cabriolet in general. With that ridiculously good engine/exhaust noise, interior and exterior styling that's subtly enhanced by AMG goodies and a chassis that skews slightly more towards spirited driving, it's a sublime machine that feels worth every single penny of its considerable £135,675 asking price. Yup, the S 63 Cabrio is another world-beater from Stuttgart.
Exterior Design
Interior Ambience
Passenger Space
Luggage Space
Safety
Comfort
Driving Dynamics
Powertrain
