The new BMW 6-Series Convertible is available with two engine variants from launch. The eight-cylinder powerplant in the BMW 650i Convertible produces 300 kW/407 hp, while an exclusive variant of the six-cylinder in-line engine with BMW TwinPower Turbo, direct injection and VALVETRONIC -generating 235 kW/320 hp – has been developed for the BMW 640i Convertible. Both engines team up as standard with an eight-speed Sports automatic gearbox. Standard-fitted BMW EfficientDynamics features include the Auto Start-Stop function in the BMW 640i Convertible.
At 4,894 millimetres (192.6 in.) in length, the new BMW 6-Series Convertible is 74 millimetres (2.9 in.) longer than its predecessor. Its similarly extended wheelbase now stretches to 2,855 millimetres (112.4 in.). The car has also grown by 39 millimetres (1.5 in.) in width, and now measures 1,894 millimetres (74.5 in.) across, while 9 millimetres (0.35 in.) have been shaved off its height (now 1,365 mm / 53.7 in.). These dimensions not only create a significantly more powerful and, at the same time, elegantly sweeping overall impression, they also take interior spaciousness to new levels. Despite its lower height, the new BMW 6-Series Convertible offers greater headroom in both the front and the rear. Added to which, the height adjustment of the driver and front passenger seats cover a greater range. The increase in the width of the interior is noticeable from all four seats, and passengers in the rear seats also benefit from additional legroom. The tilt angle of the rear seat backrest has seen further optimisation over the predecessor model and now achieves virtually the same angle as you will find in BMW saloons.
The 4.4-litre eight-cylinder engine in the new BMW 650i Convertible develops a maximum 300 kW/407 hp between 5,500 and 6,400 rpm, and puts its peak torque of 600 Newton metres (443 lb-ft) on tap between 1,750 and 4,500 rpm. This unique engine, whose turbochargers are positioned in the V-shaped area between the cylinder banks, produces an instantaneous and sustained wave of power, making it a feast for the enthusiast driver. The new BMW 650i Convertible completes the sprint from 0 to 100 km/h (62 mph) in 5.0 seconds, and the engine electronics eventually step in to halt acceleration at 250 km/h (155 mph). This range-topping engine also boasts extraordinary efficiency for a model in its output class, as average fuel consumption of 10.7 litres per 100 kilometres in the EU test cycle (26.4 mpg imp) and CO2 emissions of 249 grams per kilometre clearly show.
The six-cylinder in-line engine under the bonnet of the new BMW 640i Convertible complements its BMW TwinPower Turbo technology and petrol direct injection with VALVETRONIC fully variable valve control. All of which enables the 3.0-litre unit to develop a maximum 235 kW/320 hp at 5,800 rpm and maximum torque of 450 Newton metres (332 lb-ft) between 1,300 and 4,500 rpm. This engine propels the BMW 640i Convertible from 0 to 100 km/h (62 mph) in 5.7 seconds and on to an electronically limited top speed of 250 km/h (155 mph). Its average fuel economy in the EU test cycle comes in at 7.9 litres per 100 kilometres (35.8 mpg imp), while CO2 emissions are 185 grams per kilometre.