It has to be said, that BMW is not known for being reticent about it's products and the information blurb is loaded with hyperbole and superlatives, this is especially true when it comes to the engines.
It has to be said, that BMW is not known for being reticent about it's products and the information blurb is loaded with hyperbole and superlatives, this is especially true when it comes to the engines."The world's most efficient V8 petrol engine" is how the 4.4-litre, twin turbo with High Precision Injection is described. It can be found under the bonnet of the BMW 750i where it produces 407PS, which is up by almost 41PS over the previous model, and 600Nm of torque.
Similarly, the "most powerful straight-six petrol engine in the BMW line-up", is the 3.0-litre, twin turbo with HPI, which powers the BMW 740i. On tap is a power output of 326PS (20PS more than before) and 450Nm.
Finally, there is the 3.0-litre, which is the first of a new generation of straight-six diesel engines and the one under the bonnet of the BMW 730d, test car. It is said to be the most economical car in its segment, while still providing 245PS at 4,000rpm and 540Nm of torque between 1,750 and 3,000rpm.
It is the slowest car of the three in the sprint, taking 7.2 seconds to reach 62mph from standstill and from there the top speed of 152mph is not far away. Although, in relation to the petrol-engined cars, the BMW 730d might be a little slow off the mark, it is by far the most economic and, taking into account the size of the BMW 7 Series, it can almost be considered frugal.
The official figures are measured in road trim and with 75kg to represent driver and luggage and so we have 29.7mpg for the urban cycle, 47.9mpg for the extra-urban and 39.2mpg for the combined cycle, while 192g/km CO2 is emitted from the dual tailpipes. According to independent figures supplied by BMW, the 730d beats the Mercedes 320CDi and the Audi A8 3.0TDi, in terms of power, torque sprint time, top speed, emissions and combined fuel consumption.
For the most part, this down to the EfficientDynamics ethos of weight-saving measures, Brake Energy Regeneration and engineering but without the loss of driving enjoyment, dynamics and safety. Driving enjoyment is guaranteed, whether it is motorway cruising or exploring the performance on country lanes. The electronic wizardry has a lot to do with it but it is not obvious in the feel of the car, which is how it should be.
BMW 7 Series Road Test Data
|Model Reviewed||BMW 730d|
|Performance (manufacturers data)|
|0 - 62 mph||7.2 Seconds|
|Top Speed||153 mph|
|Transmission||6-Speed Automatic With Steptronic|
|CO2 Emissions (NEDC Figures)||g/km|
|Economy (NEDC Figures)|
|Extra Urban||47.9 mpg|
|Euro NCAP Rating||TBA|
|Warranty||3 years / Unlimited miles|
|Price (when tested on the 06/05/09)||£54,160|