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New BMW 7 Series with 134.5mpg

The forthcoming BMW 7 Series, the 740e, will be capable of 134.5mpg and 49g/km CO2 emissions as well as having 326hp, 500Nm torque, and a 0-62mph time of 5.6 seconds. The new BMW 730d has a combined fuel economy figure of 60.1mpg, equating to 124g/km CO2

The new BMW 7 Series is both stronger and up to 130kg lighter than its predecessor thanks to the intelligent use of multiple materials in the construction of the body, including carbon-fibre reinforced plastic (CFRP) for the Carbon Core. This advanced construction is complemented by six-cylinder petrol and diesel engines taken from the latest generation of BMW power units.

The environmental impact – the “greenhouse potential” – is around 25 per cent lower than in the outgoing model.

The BMW EfficientLightweight concept means that the models in the new BMW 7 Series line-up are up to 130kg lighter than their predecessors, despite boasting a significantly greater number of comfort and safety features. The key element here is the special body structure known as the Carbon Core. Thanks to its composite construction featuring CFRP, ultra-high-tensile steels and aluminium, the intelligent body design succeeds in increasing the strength and rigidity of the passenger cell while also bringing about a substantial reduction in vehicle weight. By using a hybrid construction of CFRP with ultra-high-tensile steels for structural elements, such as those in the vicinity of the B-pillars, the design of the sheet-metal components can be adapted to save weight.

The Carbon Core body is based on technology transferred from BMW i car development. The new BMW 7 Series is the first ever vehicle in which industrially manufactured CFRP is used together with steel and aluminium. It combines with the use of aluminium for specific sections of the body and chassis along with the systematic improvement of smaller details. Apart from the doors, the bootlid is also made from aluminium for the first time, and its use for assorted suspension components reduces the unsprung masses by as much as 15 per cent – to the benefit of suspension comfort. The vehicle’s centre of gravity is now even lower, and the load is distributed 50:50 between the two axles for perfect balance.

The six-cylinder in-line engines, with BMW TwinPower Turbo technology, that are fitted in the new BMW 7 Series range stem from the BMW Group’s latest generation of engines. The 3.0-litre petrol unit under the bonnet of the BMW 740Li produces an output of 326hp, 7hp more than the engine it replaces.

The diesel unit powering the BMW 730d and BMW 730Ld models has a 3.0-litre capacity and likewise boasts a 7hp increase in output, in this case to 265hp, combined with superior efficiency. Peak torque is now 620Nm, and fuel consumption and emissions are considerably lower as well thanks to a reduction in weight, improved thermodynamics for the turbocharging system with VNT technology and a new common-rail direct injection system with piezo injectors that now generate a maximum pressure of 2,500 bar. The new diesel models in the BMW 7 Series line-up are available with xDrive as an option with the exception of 730Ld.

There are also two new plug-in hybrid models: the BMW 740e, and the BMW 740Le xDrive – proof that it’s not just the Carbon Core that has been gleaned from the development of BMW i cars, but also BMW eDrive powertrain technology. The intelligently controlled interaction between a 2.0-litre petrol engine with BMW TwinPower Turbo technology and an electric drive unit integrated into the eight-speed Steptronic transmission endows the BMW 740e with dynamic acceleration yet very low consumption and emissions figures in everyday driving. While producing a total system output of 326hp, it returns a combined fuel consumption of 134.5mpg in the guise of the BMW 740e or a combined electric power consumption of 12.5 kWh. CO2 emissions are just 49g/km.

The energy for the electric motor is drawn from a lithium-ion high-voltage battery housed underneath the rear seat where it is very well protected in the event of a crash. It can be recharged by connecting to any standard domestic power socket or a BMW Wallbox, as well as at public charging stations.

The eDrive button on the centre console lets the driver adjust the hybrid drive’s operating mode. In the AUTO eDrive basic setting, the engine’s power is boosted to notable effect by the electric drive when accelerating or during quick bursts of speed. With the MAX eDrive mode engaged, meanwhile, the BMW 740e is able to run purely on electric power, meaning zero local emissions, at speeds of up to 75 mph and for a maximum range of up to 25 miles (BMW 740Le xDrive: up to 23 miles).

The driver is also able to select the Battery Control mode, which raises or maintains the high-voltage battery’s state of charge as required. In this way, electrical power can be deliberately conserved for all-electric driving later in the journey. Whenever route guidance is active in the navigation system, the predictive power management function calculates a journey-specific strategy for electric driving through to the entered destination.

The standard specification for the BMW 740e and BMW 740Le xDrive furthermore includes an auxiliary heating and ventilation system, which is powered by electricity from the high-voltage battery or from the mains supply while charging.

The standard-fit eight-speed Steptronic transmission contributes to further efficiency savings with its wider ratio spread, reduced weight and optimised calibration. A new transmission control system makes for more comfortable shifting and allows the transmission to be linked up with the standard Navigation system. An eight-speed Steptronic Sport transmission with shift paddles on the steering wheel is available as an option (standard on M Sport models), which also features a Launch Control function.

Features such as Brake Energy Regeneration and Auto Start Stop ensure highly efficient energy management. Activating the ECO PRO mode with the Driving Performance Control switch allows use of the coasting function, which decouples the powertrain in overrun phases while travelling at speeds between 31–100mph. This mode’s range of functions – which are now individually programmable for the first time – additionally include efficiency-oriented operation of comfort features, efficiency tips, as well as the Route-ahead Assistant, which gives recommendations for an efficient driving style based on the navigation data.

BMW UK aims to sell around 1,400 7 Series models in its first full year of sales.  The new BMW 7 Series goes on sale on 24 October 2015. Prices start at £64,530.

BMW 7 Series

BMW 7 Series

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