What is it?
The sixth installment in one of Mercedes’ best known and most desired model lineages: this is the new SL. It promises to scale new heights in terms of performance and efficiency, refinement and dynamism – but moreover, to offer an even more convincing blend of the intoxicating luxury and open air sporting thrill for which Mercedes’ grand convertible has become so widely revered.
The ‘R231’ is a massive undertaking for Mercedes – the firm’s first series-production model to be made almost exclusively from aluminium. The SL’s sophisticated body-in-white superstructure mixes die cast-, chill cast-, stamped- and extruded aluminium with a little magnesium and ultra-high strength steel. A lighter all-magnesium folding hard-top roof and mostly aluminium body panels contribute, in turn, to an overall kerbweight saving of up to 140kg, old car to new. More importantly, the new underbody has increased the car’s torsional stiffness (absolutely critical for delivering good dynamic performance in a convertible) by more than 20 per cent.
Two versions of the SL will be available in the UK this July, but the 4.7-litre twin-turbocharged V8 in the ‘500’ represents the biggest step forward in both performance and efficiency. With 429bhp and a huge 516lb ft of torque, it catapults the SL to 62mph in just 4.6sec – as fast as the last SL63 AMG. It’s also capable of 31mpg on the combined cycle.
Suspension, like that of the last car, is all-independent, by multi-links at both ends. Steel springs with adaptive dampers are standard on both the V6 SL350 and the SL500; Mercedes’ air-sprung Active Body Control chassis is optional on both cars, but standard on the range-topping new SL63 AMG, which arrives in the autumn.
And the cabin? That remains a strict two-seater. Need occasional back seats? Then you’re not SL people; feel free to shop elsewhere. It’s an arrogant and unusual stance, but one this opulent roadster nonchalantly backs up.
What’s it like?
On top of the all-new underbody, the SL’s basic concept and proportions are carried over. The car is long of bonnet, short of cabin, with the same slightly unwieldy looking bustle back-end, the dimensions of which are necessary to package the car’s metal roof when folded.
In truth, the styling of the new car barely does justice to Mercedes’ investment in it. The new grille and headlights freshen the car, and the cleaner interpretation of the bodyside is welcome, bringing with it a pleasing nod to the gorgeous 1960s ‘Pagoda’ SL. But considered as a whole, the new SL seems plain; next to the SLK and SLS, like just another drop-top clone. It deserves better.
Thankfully, the car has lost none of its glorious distinctiveness from behind the wheel. You feel fortunate just to be on board. The cabin’s even wider than it used to be, so you sit at a very discreet distance from your passenger, surrounded on all sides by plush leathers, cool metal trim and attractive, aero-inspired instruments.
Thus ensconced, thumb the silver starter button. The V8 engine in the SL500 catches with a muffled roar. It’s nearly silent at idle, a little more audible at urban speeds, and only really raises its voice when you flex the long-travel, floor-mounted accelerator – and only then in the most suave and cultured tones.
Eerily smoothness and restraint characterises so much of this car’s demeanor. It’s the kind of smoothness that eases the SL away from stationary with pillowy gentility, and that swaps gearbox ratios on a part throttle almost unacknowledged. As any automotive engineer will tell you, it’s also the kind of smoothness that only painstaking development can produce. And it’s universal in the new SL: all-pervading. Even over the most neglected tarmac, nothing disturbs the car’s perfect cruise.
So immaculate is the ride comfort of this new SL that it’ll glide unperturbed over the very worst surfaces. One such road we sought out – an old, narrow, sunken backroad warped by the Spanish sun – looked like it might provide a worthy test, but the SL covered it like freshly rolled motorway. The car bobbed ever-so-gently on its springs, effortlessly translating severe shocks to its chassis into perfectly cushioned, barely delectable bodily reactions. Even with the roof down there wasn’t the faintest suggestion that the car’s structure was being stretched; not a shudder from the steering column, or a shimmy from the rearview mirror. Open-top motoring just doesn’t get any more refined.
A car so wedded to comfort – so adept at absorption and isolation - could never lead the class on poise, response, feel: almost diametric opposites of everything that the modern SL is about. The car’s heartland customers wouldn’t want it to. If it meant compromise, neither would we.
And yet the SL really does handle - up to point. Mercedes served up both steel- and air-sprung versions of the car on the SL’s first press launch. While the Active Body Control system certainly serves up wider spread ‘Comfort’ and ‘Sport’ chassis settings, it was the standard steel-sprung setup we preferred, delivering better steering feedback, more progressive damping and more consistent wheel control.
With either suspension system, the SL500 takes to brisk driving in easy, undemanding style. It’s not a great car to hustle and harry: left in ‘D’, the automatic gearbox can be a bit slow to kick down. But if you aim for well-prepared swiftness rather than a frenzied hurry, the SL seems to respond. You learn to make the best use of that engine’s massive swell of torque without hitting the accelerator’s kickdown switch, and to carve a consistent and clean line through bends.
500 footpounds of torque can be seductive, of course – and it’d probably send this mid-range, non-AMG Merc from a standstill to 100mph in less than ten seconds. But the SL500’s brakes are strong and resistant to fade, and even if you do arrive at a corner a little faster than planned, you’ll find the SL’s grip levels quite high, and its chassis balanced up to the limit.
You’ll know you’ve reached that limit when guiding the SL’s nose becomes tricky. The steering’s weight and on-centre accuracy begins to fluctuate. Bumps that wouldn’t register at lower speeds start to thump away distantly within the car’s wheelarches, and disturb the car’s stability slightly. And understeer gradually builds, waking the ESP system. All at speeds and in situations that may not trouble Aston Martin Vantage Roadsters, Porsche 911 Convertibles and Jaguar XKs – as if that would bother your average SL convert.
Should I buy one?
Absolutely. Because, however highly you value ultimate dynamic poise and precision, the SL’s final-tenth dynamic wooliness doesn’t dim its appeal in the slightest.
While it may not be overly endowed with body control, chassis composure and bristling feel, Mercedes’ magnificent roadster remains utterly unique. Almost sixty years young, it’s become just about the most splendid, single-minded luxury convertible in the world. In this tester’s experience, not even Bentley, Aston Martin or Rolls-Royce provide better.
Mercedes SL500 BlueEfficiency
Price: circa £82,000; Top speed: 155mph (limited); 0-62mph: 4.6sec; Economy: 31.0mpg; CO2: 212g/km; Kerb weight: 1785kg; Engine type, cc: V8, 4663cc, twin turbocharged petrol; Power: 429bhp at 5250rpm; Torque: 516lb ft at 1800-3500rpm; Gearbox: 7-spd automatic