With the M3 Sedan and M4 Coupe already fully unveiled and headed for showrooms, the M4 Convertible is undergoing its last rounds of testing before its official debut later this year. The hard-top convertible should add about 500lbs to the coupe model's weights. We expect it to be displayed at the March Geneva Auto Show, where it will join the rest of the M family before shipping out to American shores.

The convertible will feature the company's 3.0-liter twin-turbo six-cylinder engine, making 425 horsepower and 425 lb-ft of torque. A six-speed manual or seven-speed dual clutch transmission will send power to the rear wheels. Zero-to-sixty times are expected to be just upwards of four seconds, with top speeds of 155 mph. These numbers all represent significant improvements from the previous generation, V-8-powered M3 convertible. With most of its camo shed, the car looks pretty much identical to its coupe twin, only with some slightly-awkward roof lines and pillar changes to accommodate the folding hard top.