The petrol units include a twin-scroll turbocharged 3.0-litre inline six-cylinder that develops 316bhp and 332lb ft in the 640i, and a twin-turbocharged 4.4-litre V8 with 444bhp and 479lb ft in the 650i, which is claimed to hit 62mph 0.3sec faster than before at 4.6sec while going on to a top speed limited to 155mph in rear-wheel drive coupé guise.
Also available is a sequential turbocharged 3.0-litre in-line six-cylinder diesel engine. It produces 309bhp and 464lb ft in the 640d, which is claimed to offer a 2.0mpg improvement in combined cycle fuel consumption at 54.3mpg, allied to average CO2 emissions of 146mpg in the standard rear-wheel drive coupé.
As before, all new 6 Series models come as standard with an eight speed automatic gearbox boasting remote steering wheel mounted shift paddles. A raft of fuel-saving features from BMW’s EfficientDynamics program also feature, including automatic stop-start and a coasting function as part of the Eco Pro driving mode – one of five different modes from which the driver can choose.
Buyers can also specify BMW’s xDrive four-wheel drive system. While adding 75kg to the kerb weight, it serves to enhance traction, bringing about an improvement in the standing-start acceleration on each of the new 6-series models.
The fastest-accelerating of all is the 1855kg 650i xDrive coupé with a claimed 0-62mph time that undercuts that of the standard rear-wheel-drive 650i coupé by 0.2sec at 4.4sec.
In line with standard 6 Series models, the new M6 coupé, cabriolet and GranCoupé continue to run BMW M division’s twin-turbocharged 4.4-litre V8 petrol engine with 552bhp and 501lb ft of torque.
Eschewing the eight-speed torque converter-equipped automatic gearbox of lesser 6 Series models, the rear-wheel-drive-only M6 channels drive through a seven-speed dual-clutch automatic gearbox and electronically controlled M-differential.
Performance and economy remain the same as before, with the facelifted M6 coupé boasting a claimed 0-62mph time of 4.2sec, a limited 155mph top speed, combined fuel consumption of 28.5mpg and average CO2 emissions of 231g/km.
As before, buyers of the M6 can opt for an optional Competition Package. It raises peak power by 15bhp to 567bhp, bringing about a 0.1sec improvement in 0-62mph acceleration. Further changes include detailed suspension tweaks, more direct steering ratio and unique 20-inch wheels.
All 6 Series models come in the same trims as before, with SE, Sport, M Sport offered on the standard cars. All models all come with LED headlights included while the SE models get a new leather instrument panel with contrast stitching. The Sport models add the contents of the old Sport pack as well as bi-colour Nappa leather comfort seats with lumbar support and 19in alloys. M Sport models get Nappa leather upholstery.
The equivalent coupe and four-door Gran Coupe models cost the same throughout the range, ranging from £59,430 for the 640i SE to £72,390 for the 650i M Sport. The equivalent convertible model adds between £5600 and £5900 to the price.
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