BMW updates 7 Series; completely new powertrain for ActiveHybrid 7

25 May 2012

The new BMW ActiveHybrid 7. Click to enlarge.

BMW is updating its flagship BMW 7 Series for 2013 with significant powertrain upgrades in the 740i/Li and 750i/Li models—including BMW’s 8-speed Steptronic automatic transmission; and xDrive, BMW’s intelligent all-wheel drive system, now available for the 740Li—as well as a completely new powertrain for the ActiveHybrid 7. The new 2013 7 Series arrives in US BMW center showrooms in late summer 2012, expect for the ActiveHybrid 7, which arrives in early fall.

The updated BMW ActiveHybrid 7 features BMW’s 3.0-liter TwinPower Turbo inline 6-cylinder engine combined with full-hybrid power for lower fuel consumption and emissions, as well as innovative auxiliary functions. In this application, the engine is the same 315 hp (235 kW) version as in the new BMW 740Li and replaces the V8 engine previously used in the ActiveHybrid 7.

Other hybrid components include a 55 hp (41 kW) synchronous electric motor, hybrid-spec 8-speed Steptronic automatic transmission, a lithium-ion high-performance battery and power electronics which run the intelligent energy management.

With combined output of 349 hp (260 kW) and peak torque of 367 lb-ft (498 N·m), the new BMW ActiveHybrid 7 accelerates from 0 to 60 mph in about 5.5 seconds (preliminary). At the same time, it delivers significantly improved fuel efficiency. US EPA numbers are not yet available. However, in the EU test cycle the new ActiveHybrid 7 yields efficiency gains of 14% over the new 740Li which itself sees an improvement over its predecessor.

The electric motor provides an extra 155 lb-ft (210 N·m) of torque through the boost function if the driver should need a quick sprint or to call on strong mid-range acceleration, when passing or merging for example. ECO PRO mode, with coasting function and proactive analysis, prepares the drive system in advance for upcoming situations on the road. Brake Energy Regeneration and the Hybrid Start-Stop system also work together to maximize overall efficiency.

The 2013 BMW ActiveHybrid 7 can also run purely on electric power. If the hybrid battery has sufficient charge and the driver goes easy on the accelerator, the car can cover a distance of up to 2.5 miles (4 km) in all-electric mode, with a top speed of 37 mph (60 km/h).

The BMW ActiveHybrid 7 features a coasting mode which completely shuts off the combustion engine when coasting, allowing the ActiveHybrid 7 to glide along emissions-free. Intelligent energy management allows the ActiveHybrid 7 to analyze the driving situation ahead in order to prime the hybrid drive components for maximum efficiency. This is accomplished by integrating the power electronics with the navigation system.

Based on data, such as route topography, speed limits or traffic levels, the vehicle can be prepared in advance and the available energy deployed as efficiently as possible. For instance, a longer downhill stretch can be used to recharge the hybrid battery so that the ActiveHybrid 7 can be driven on purely electric power through a residential area on the “home stretch”.

The new ActiveHybrid 7 will be available in the US as a long-wheelbase model only.

Other powertrains. While the 760Li, with its 6.0-liter Twin Turbo V12, remains the pinnacle in the BMW 7 Series line, both inline-6 cylinder 740i/Li and V8-powered 750i/Li models receive significant enhancements, designed to deliver both better performance and greater efficiency. Every 7 Series model now features an intelligent 8-speed Steptronic automatic transmission that offers significantly reduced fuel consumption and emissions. Auto Start-Stop, Brake Energy Regeneration and the second-generation Driving Dynamics Control with ECO PRO mode offer additional potential for fuel-saving.

The 2013 BMW 740i/Li now feature BMW’s latest 3.0-liter TwinPower Turbo inline 6-cylinder (N55). Compared to the previous model, this new engine combines a single twin-scroll turbocharger, High-Precision Direct Injection and Valvetronic, BMW’s throttle-less intake system. This engine again uses Double-Vanos infinitely variable camshaft timing.

The 740i/Li use a high-output version of this engine delivering 315 hp and 330 lb-ft (447 N·m) of torque for power on par with the previous model. US EPA mileage estimates are not yet available. However, in the EU test cycle, fuel consumption was reduced by about 20%. Another significant option for customers in the US is the availability of xDrive, BMW’s intelligent all-wheel drive system, for the 2013 BMW 740Li.

The 2013 BMW 750i/Li also receive upgrades to their powertrain that enhance performance while improving efficiency. The 4.4-liter TwinPower Turbo V8 has been updated with Valvetronic. It works in concert with High-Precision Direct Injection and twin turbochargers, nestled on top of the engine, to deliver 445 hp (332 kW), a 45 hp increase over its predecessor, and 480 lb-ft (651 N·m) of torque, an increase of 30 lb-ft.

Acceleration from 0-60 mpg is 4.7 seconds (preliminary), while consuming significantly less fuel. US EPA mileage estimates are not yet available. However, in the EU test cycle, fuel consumption was reduced by 25%.

Auto Start-Stop, Brake Energy Regeneration, ECO PRO mode. All new BMW 7 Series models come equipped with Auto Start-Stop which can cut fuel consumption by up to 6% as well as Brake Energy Regeneration. Generally the battery is only recharged when the driver is off the throttle, for example, when coasting or under braking. Driving Dynamics Control in the new 7 now includes ECO PRO mode which modifies the powertrain management as well as the programming of the heating and air conditioning, heated seats and exterior mirror heating to operate with optimum efficiency. It also offers tips for an efficient driving style. Taken together, ECO PRO can reduce fuel consumption by as much as 20%.

Driving Dynamics Control allows the driver to tailor accelerator response characteristics, engine response, power steering characteristics, and the Dynamic Stability Control thresholds. The Servotronic function, Integral Active Steering, automatic transmission and Dynamic Damper Control are also integrated into the system.

Using the rocker switch on the center console, drivers can choose between ECO PRO, COMFORT+, COMFORT, SPORT and SPORT+ modes. Each mode activates different settings for the relevant powertrain and chassis components. The distinction between each of the modes is more perceptible than before.

The addition of ECO PRO mode helps the BMW 7 Series driver maintain an efficient driving style. It does so by changing the accelerator mapping so that the same pedal travel delivers less power than in the standard mode. The control strategy for the automatic transmission is also modified to upshift sooner and downshift later, while intelligent energy and climate management reduces power consumption as well as the energy consumption of electrical systems such as heated mirrors and seats.

To facilitate the most efficient driving possible, ECO PRO provides tips and incentives on how to develop a more efficient driving style for the situation at hand. Special displays in the instrument cluster let the driver know how well they are doing by indicating how much the driving range is being extended and by showing a history of their fuel consumption. In ECO PRO mode, average fuel consumption can be reduced by up to 20%.

The ECO PRO mode in the new BMW 7 Series includes the new coasting mode, which is designed to decouple the engine when coasting at speeds between 30 – 100 mph (48 – 161 km/h). In coasting mode, the engine in the new 7 Series freewheels on deceleration with no engine braking effect thereby reducing fuel consumption. Through proactive driving, the kinetic energy built up by the vehicle can be harnessed to achieve fuel savings of as much as five percent. The coasting function is shown graphically in the information display and can be switched off if desired.

The 7 Series is the first car to feature an electronically controlled damping system whose shock absorbers are adjusted individually at each wheel based on the condition of the road surface and the driving style.

Each wheel’s compression and rebound settings are adjusted continuously and independently from one another. For example, a stiff chassis setting can be combined with comfortable responses to unevenness in the road surface. The shock absorber settings can be preset by the driver using the Driving Dynamics Control switch.

Active Roll Stabilization, which standard on the 760Li and optional on other models, reduces body roll in high-speed corners and under sudden changes in direction. Sensors calculate the amount of body roll which is quickly counteracted by rotary actuators in the front and rear anti-roll bars. This system allows drivers to thread the car through corners with even greater agility and precision.

Integral Active Steering is available for rear-wheel drive BMW 7 Series models, which combines the Active Steering system for the front wheels with rear wheel steering. The steering angle and power assistance are controlled at both the front and the rear with the help of electric motors. The optimized system control unit processes information on wheel rotation speeds, steering wheel movement, yaw rate and lateral acceleration to ensure optimum steering behavior for the driving situation at hand. Integral Active Steering also works with a variable steering ratio on the front wheels, which makes parking and maneuvering easier and enables impressive precision at higher speeds.

All BMW 7 Series models are now equipped with self-leveling rear air suspension, which keeps the car riding at a constant height no matter what kind of driving conditions it encounters and regardless of the loads on board. This automatic self-leveling suspension responds to any change in load by adjusting the suspension at the relevant wheel. This means that only small interventions are required in response to spring movements caused by road imperfections and cornering lean. This feature was previously available only on long wheelbase models in the US.

3D nav system. The latest-generation navigation system in the 7 Series features a revised design and operating system. The user interface includes revised graphics and now comprises 3D elements, while the entire architecture of the individual menus is now presented in virtual, three dimensional spaces. Its 1.3 GHz processor and dedicated 3D graphics card, bring new levels of animation and dynamic transitions.

New function bars are superimposed on the map as an extension of the original map bar and open up additional options. This allows for Real Time Traffic Information (RTTI) or weather updates to be superimposed, points-of-interest to be displayed, or the map to be quickly switched from top view to perspective view.

The latest-generation navigation system features a full speech recognition function and optimized voice control system to complete the portfolio of office functions offered by BMW ConnectedDrive as BMW. The full speech recognition system now includes the dictation function which gives drivers the opportunity to dictate text freely and compose short text-based messages simply by saying what they wish to write. Just a few seconds after dictation has been completed, the transcribed text appears in the display and can be read out if desired. Drivers also have a number of simple-to-use, speech-based editing tools available to them for putting the final touches to e-mails and SMS messages easily and, most importantly, safely. The multilingual system can recognize six languages including English and Spanish.

The navigation system now allows additional menu functions to be called up through simplified voice commands. The system is able to recognize contact data irrespective of the format in which it is stored, and thus independently of first name and surname order. Additional submenu functions can now be activated or actions specified by speech input—from adjusting the radio and entering a destination to changing the route criteria. Voice control is becoming even easier to use.