BMW reveals the images of M4 Convertible

Hot on the heels of the latest BMW M3 Saloon and M4 Coupé, both of which were revealed at Detroit at the start of the year, details of the M4 Convertible are now released, the fifth-generation high-performance open-top car of its kind from the company’s M division.

Powered by the same 431hp in-line six-cylinder engine as the M3 Saloon and M4 Coupé, the Convertible offers the option of a six-speed manual or seven-speed M Double Clutch transmission. The M4 Convertible exhibits all the hallmarks of a car created by BMW’s high-performance specialists – lightweight engineering, carefully honed aerodynamics, advanced race-derived chassis tuning and electronic driver assistance technologies and a sporty elegant profile, open or closed.

The BMW M4 Convertible derives its firepower from a high-revving six-cylinder TwinPower Turbo engine which benefits from technologies developed on the race track. This 2,979cc in-line six-cylinder powerhouse, developed by BMW M, features two mono-scroll turbochargers, high-precision direct injection, VALVETRONIC fully variable valve timing and Double-VANOS variable camshaft control. This technical prowess allows the M4 Convertible to switch seamlessly from an undemanding everyday road car to one, which feels totally at home on the racetrack.

Huge reserves of torque peaking at 550Nm are available from just 1,850rpm – exactly the point at which maximum power of 431bhp is attained. This is then maintained until 7,300rpm. Maximum engine revolutions are 7,600rpm. All of this means the M4 Convertible delivers a seemingly never-ending surge from little more than engine tickover to the electronically restricted top speed of 155mph. The zero to 62mph sprint is achieved in 4.6 seconds with the six-speed manual gearbox, or 4.4 seconds with the seven-speed M Double Clutch Transmission.

Such impressive performance calls for advanced, race-derived technologies, including special cooling systems. An indirect intercooler maximises charge pressure and engine output, while the main radiator is supplemented by other coolers located in the sides of the engine bay for the high and low-temperature water circuits as well as for the engine and transmission oil (with the M DCT gearbox). An additional electric coolant pump helps to cool the turbocharger bearing mounts when the car comes to rest.

The lightweight magnesium sump has a special cover to minimise the movement of oil during high-G cornering, and an additional pump and sophisticated oil return system maintain stable oil circulation under hard acceleration and braking. The quad exhaust system contains electronically controlled flaps which minimise back-pressure and ensure that the M4 Convertible has an unmistakable BMW M sound.