This is the new BMW M4 Convertible, the topless sister-car to the M4 coupe (and M3 saloon) we saw at the 2014 Detroit motor show.
Of course, the drivetrain is retained from the fixed-head cars, meaning a 3.0-litre twin-turbo straight-six up front, 426bhp and 406lb ft, and a choice of six-speed manual or seven-speed dual-clutch transmissions with paddeshifters to play with. As prescribed in the German performance car handbook, the M4 Convertible strolls on to 155mph flat out.
So, let’s concentrate on that folding roof – and how BMW has tried to make the M4 Convertible as sharp as its hardtop brethren.
What’s new under the skin of the 2014 BMW M4 Convertible?
Thanks to the M3 and M4’s carbonfibre engine strut brace, propshaft, plastic front wings and numerous other attention-to-detail changes, the M4 Convertible weighs in 60kg lighter than the old V8 M3 Convertible.
While we’d hardly call 1750kg of rear-drive German cabriolet featherweight, it is at least less obese than the (admittedly all-wheel drive) 1852kg Audi RS5 Cabriolet.
The M4’s weight saving and less thirsty engine mean fuel consumption is now up to 32.5mpg on the claimed combined cycle, rather than the old M3 Convertible’s pitiful 23mpg. CO2 emissions fall from 293g/km to 213g/km, or 203g/km if you spec the dual-clutch gearbox for an extra £2645.
It’s faster than the last open-top M3 too. Forget 5.1sec 0-62mph: the M4 does it in 4.6sec as a manual, or 4.4sec as an auto. Thank the 111lb ft torque increase for that.
Tell me more about the roof
It opens or closes in 20sec, converting a 220-litre boot into a 370-litre space in its absence. You can do the Full Monty at up to 8mph, and when the roof is raised, its 2dB quieter inside the new M4 than it was inside the old M3 with the roof up.
What other toys do I get?
Standard spec includes upgraded M Performance brakes (carbon-ceramics are an option) and 19in alloys, plus heated front seats, BMW’s ‘Professional’ infotainment system, and adaptive suspension.
Chief among the interesting options is a seat-housed heater that wafts warm air around front seat occupants’ shoulders when driving with the roof down on a brisk, crisp morning. Mercedes has offered a similar system for years in the SL and SLK, and patented the name ‘AirScarf’ for it. So, BMW has gone away, had a think, and called its rival system ‘Air Collar’. Clever!
How much for this roofless hair-raiser?
At £60,370 before options, the M4 Convertible is the most expensive new M3/M4 of the trio, but comfortably cheaper than the £68,985 Audi RS5 Cabriolet. It arrives in UK showrooms in September 2014.