BMW M6 Convertible

BMW says the new, second-generation M6 convertible is the fastest-accelerating open-top road car it has ever built. Which is a fair enough statement given that it hits 62mph from standstill in 4.3sec, rockets from 50-75mph in fourth gear in a rather special 3.8sec and runs the standing kilometre in 22.1sec – in each discipline outpacing the old M6 convertible, its previously fastest series production open-top.

It also reaches 189mph, according to the head of BMW’s M division, Friedrich Nitschke, when running an optional M Driver’s Package. Serious numbers, no less…

The remarkable thing is that the latest M-car manages all this while laboured with a kerb weight of 1980kg – a figure that places it firmly in the heavyweight class, some 185kg above that of perhaps its keenest open-top rival, the Jaguar XKR-S convertible.

But with a 552bhp twin-turbocharged 4.4-litre V8 petrol engine, the M6 convertible is claimed to possess colossal straight-line speed. Given its breathtaking £98,995 price tag – a good £10,000 more than its direct predecessor here in the UK – you could argue that it ought to be.

Is the new open top BMW really as quick as the official performance claims make out? Initial impressions suggest it is; with 52bhp and 118lb ft more than the old model’s naturally aspirated 5.0-litre V10 it is terrifically potent.

It’s not the sort of car that screams for attention – M-cars rarely have. But the styling changes  give it a more menacing air. Included is a deeper front bumper with larger engine cooling ducts, a 30mm increase in the front track, BMW M division’s signature chrome gills and a new rear bumper with an integrated diffuser.

The cabin of any M car should be special. The steering wheel,  instruments, gear lever and the front seats are unique to the M6. The most important functions, those that allow you to alter the driveline and chassis characteristics, are grouped together around the gear lever. Not so clever is the positioning of the switch for the fully automatic fabric roof, which sits where your elbow rests on the centre console.

On the open road, the M6 convertible’s forced induction engine possesses an alluring range of sounds. Under load the  V8 emits a deep mechanical growl accompanied by a high pitched exhaust note – which grows in volume and intensity was the revs built. The constant pops and crackles on downshifts are equally compelling.

As well as providing the necessary muscle for the M6 convertible, new engine also endows it with relaxed cruising properties. The vast reserves of turbocharged induced torque ensures flexibility from not far beyond idle speed, removing the need to flick through the gearbox.

The first ill fitting drain cover dispenses any lingering doubts about the M6 convertible’s structural rigidity. It was conceived at the same time as the M6 coupe and incorporates the necessary floorpan strengthening enhancements to ensure scuttle shake is never a major factor.

Roof-up refinement is exemplary by soft top standards. At motorway speeds there is little buffeting and, provided you’ve dialled up a tall gear, the otherwise frenetic exhaust note is conspicuous only by its absence. The fabric roof folds and stows in the top section of the boot at speeds up to 25mph within 19sec.