The convertible, which costs £98,995 when it goes on sale in the UK in September, shares the M5's potent twin-turbocharged 4.4-litre V8 petrol engine and seven-speed, dual-clutch gearbox.
With 552bhp and 502lb ft of torque, the engine develops 52bhp and 122lb ft more than the naturally aspirated 5.0-litre V10 of the previous-generation M6.
The new M6 convertible weighs 1980kg (50kg heavier than before) but posts official times of 4.3sec for 0-62mph and 13.1sec for 0-124mph.
The improved performance is allied to reduced fuel consumption, which is rated at 27.4mpg with emissions of 239g/km.
Carbon-ceramic brake discs are also being offered for the first time on the new M6. Available in combination with optional 20in wheels, the carbon-ceramic discs measure 410mm up front and 396mm at the rear and are claimed to weigh 19.4kg less in total than the standard steel items, for significantly lower unsprung masses.