Sadly it’s been a while since I last drove a really amazing BMW. Some have been better than others the new One Series M Coupe for example but this marque that you could once expect to lead all others has not been keeping up with its own historically stratospherically high standards. One example was the first of the new Six Series offerings to come my way a convertible which I have to say left remarkably little impression on me.
So it is with something approaching bewilderment that I have pleasure in writing that its tin-topped coupe sister when fitted with a very special engine, is a brilliantly effective and likeable device.
The motor is a three-litre diesel from which BMW has extracted no fewer than 309bhp, surely the highest specific output of any diesel-powered car on sale? But that’s not its secret: that lies in the fact that it can summon 464Ib ft of torque at 1500rpm. That’s more torque at fewer revs than the 5-litre V8 petrol in the flagship 650i can muster. Yet while the 650i does just 26.6mpg, the 640d is claimed to do 51.4mpg with correspondingly decimated CO2 figures.
Unsurprisingly, in the real world you can’t get 50mpg out of the 640d while driving anything close to normally, but 40mpg is easy which for a car of this power, weighing almost 1900kg that will fire you to 62mph from rest in 5.5sec, is pretty incredible.
This makes the 640d a hugely effective long-distance weapon. In the 600 miles it will put between fills, it will prove very comfortable, extremely quiet and sufficiently spacious even for small children to enjoy the rear seat experience. The only disappointment is that it’s not a bit more responsive to the steering. This is very much a touring car and if you try to hustle it, it responds with benign indifference. Used for its intended purpose, however as an intercontinental cruise 40 missile, it will prove very hard indeed to beat.