BMW M6 Cabriolet review (2007-2011)

It might seem ridiculous to say that a car with 500bhp feels slow. But it did. The power button was pressed but the M6 Cabriolet didn’t feel as fast as its 4.8 second 0-62mph time suggests.

Before you think I’m merely trying to point out that the drop-top version of the M6 is 0.2 seconds slower to the 62mph benchmark than its coupé relative, I’m not. I simply wasn’t as blown away by the M6 Cabriolet’s performance as I should have been.

The only reason that I can think as to why this might be is that I was at a BMW driving event. With the pick of BMW’s latest new models to drive I’d left the M6 until last, reasoning that it’s best to build up to the fastest, most powerful car in the range. I shouldn’t have, as after experiencing the new turbocharged 3.0-litre, six-cylinder units in both petrol and diesel guises in the 335 3 Series models, the M6’s 5.0-litre V10 felt a little under endowed.

We drive the 335i Coupé
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All torque

Admittedly, neither of the smaller engines can come close to the M6 V10’s monstrous 500bhp figure, but the V10’s 383lb ft of torque isn’t able to match the 335d’s 428lb ft. Even the 335i petrol can muster up 295lb from its turbocharged 3.0-litre six-cylinder unit, and it makes its presence more clearly felt than the 5.0-litre V10s. That’s simply down to the fact that the engine in the M6 is all about high rev antics. It produces its best right up above 6,000rpm, its peak torque arriving at 6,100rpm and its maximum power at an even headier 7,750rpm.

That makes the M6 Coupé the choice for committed drivers, part of its appeal being that quest for high rev pace and the soundtrack that accompanies it. But it’s different in the Cabriolet. Lopping the roof off any car inevitably changes its character, and it’s no more obvious when BMW jigsawed off the M6’s fancy lightweight carbon lid. In doing so they’ve created the most expensive car in their range, which for the record is £86,400, about £5,000 more than its Coupé relative.

What we thought of the M6 Coupé

But is it worth the extra? Certainly, like all 6 Series Cabriolets it feels rock solid. Only the very roughest of roads highlight that it’s lost some of its torsional rigidity. BMW’s M division engineers have compensated for the inevitable loss in stiffness with a slightly more compliant suspension set up. They’ve managed this without losing the M6’s sharpness, and it retains the three-mode suspension of the Coupé. So the Electronic Damper Control offering three settings – normal, comfort and sports. Normal is fine. Like the Coupé the steering remains rather devoid of feel, but turn it and the M6 reacts faithfully, even if the weighting is oddly artificial.

Too much choice

Attached to that chunky M wheel are the paddles that shift the seven ratios on offer from the M6’s Sequential Manual Gearbox. The Drivelogic programme that accompanies offers up to eleven different choices for changing gear, six manual modes and five automatic. After a fair bit of fiddling you’ll find one that suits you and leave it be, the enormous choice rather unnecessary. It’s as if BMW’s M engineers couldn’t decide which one to go for in their final set up meeting and threw them all in. I opt for the fastest shift possible, and change between the seven ratios via those paddles, the automatic option just too ponderous and indecisive for smooth driving.

And that’s a problem. Cabriolet drivers will romantically tell you that they buy open top cars for the open-to-the-elements, wind-in-the-hair experience. They’re not. It’s all about the pose. And the M6 Cabriolet out-poses most. It’s not a conventionally elegant or pretty car. It’s lines more of an assertive statement of intent. M specific details over the standard 6 add flared arches, the front ones featuring M badging, deeper front and rear bumpers and the signature quad M exhausts. The large 19-inch alloy wheels hide enormous brake discs, the M6 Cabriolet a very menacing looker. It doesn’t stop outside either, the interior too gaining some M badging and a more sporting look and feel.

Savour those sounds

Its electric roof fits neatly under the rear deck, and even when it’s down there’s a decent sized boot for the golf clubs. The rear seats remain next to useless for all but additional luggage space but the front ones are firm and supportive. There’s little buffeting with the roof down and the wind deflectors in place, the best part of the experience being the noise the engine makes. The melodious V10 plays its glorious tune through those quad exhausts, the rich tone emanating from them having a hint of F1, with a cultured bassy wuffle mixed in. It resonates beautifully, making you seek out places where it’ll bounce back; every wall, village shop or town centre a potential sounding board.

We drive the BMW M5

And that’s the odd juxtaposition with the M6 Cabriolet. Its engine is both its most appealing, and most frustrating aspect. Getting closer to that engine note is a huge part of its appeal, but on the road where it really matters it fails. The constant need to hunt around the gears to reach the high revs where the M6 engine works is at odds with the cabriolet experience. Drop-top driving isn’t about frenzied progress, it’s about easy pace and, ultimately, being seen. The M6 will get people’s attention, but it’s neither a straightforward or relaxed drive.

Verdict

As its 3 Series relatives highlight, torque is crucial, and the M6’s is too high and inaccessible to all but the most committed drivers to really allow you to enjoy its performance easily. Indeed, BMW’s own 650i Sport and Jaguar’s XKR Cabriolet fulfil the undemanding performance drop-top brief better, and are significantly cheaper. But if you really must spend in excess of £86,000 on a fast, flash cabriolet it’s difficult to ignore the Mercedes SL55 AMG. It may be a healthy £14,000 more, but it too has an engine note to die for, over 500bhp, an impeccable badge and a sub-five second 0-62mph time. It’s effortless too, and to look really good that’s crucial. And why, for me, the M6 ultimately fails in drop-top guise.

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