First Drive Review
Okay, all you folks who've been grumbling about slow evolutionary design changes at Olde Worlde companies such as BMW can sit down and shut up. We got yer all-new, totally changed, baby-out-with-the-bathwater Bimmer right here.
Engine? All-new. The bore and the stroke are familiar, but this ultralight aluminum block with cast-in silicon-crystal linings and iron-coated aluminum pistons is a newbie. Valvetronic infinitely variable valve timing and lift eliminates the drag of a throttle while providing the economy of direct fuel injection without the emissions woes of lean-burn combustion. Combined with an infinitely variable intake manifold and numerous friction-reduction measures, the 745i's horsepower is up 17 percent (to 329), and fuel economy is up 14 percent over the 740i's same-size 4.4-liter V-8.
Transmission? Revolutionary. Six widely spaced ratios in a box that weighs 18 percent less than the old five-cogger.
Suspension? Dynamic Drive also breaks ground in its use of hydraulically controlled active anti-roll bars to maintain an even keel (see Technical Highlight BMW in "Charting the Changes," October). The ride is smoothed by shocks with infinitely variable damping (a cylindrical valve inside the shock slides up and down to alter fluid flow rates).
Brakes? Innovative, in their incorporation of an electronic parking- and emergency-brake function. Press the parking-brake button with the engine running, and the ABS and stability-control hardware activate all four hydraulic brakes. Switch off the engine, and an electric motor activates a traditional cable-actuated drum-in-hat rear parking brake. This same button also activates an autohold feature that keeps the brakes applied when you come to a stop and releases when you hit the gas.
Safety? Jawohl! You have your usual front, side, and tubular head airbags — now offering protection for Mr. & Ms. Big in the back — plus new knee airbags in front. (These are only sold in seatbelt-averse North America.) To the inflatables, add active head restraints that use a pyrotechnic charge to force the front headrests forward. Front-seatbelt retractors get a pyrotechnic force limiter that moves a sleeve from a thick torsion bar onto a thinner one that twists more to relax the belt. Including the airbags, pretensioners, and a pyrotechnic battery disconnect, that brings the total fireworks count to 17, and they're orchestrated by the Intelligent Safety and Information System, a new, more powerful controller with 10 crash sensors.
And what of creature comforts? The new 7-series pushes the gadget envelope as well. Standard and optional equipment ranges from the ridiculous (power sunshades for the rear doors, power door closers, a power opening and closing trunklid) to the sublime (double-pane windows, adaptive cruise control, keyless entry and ignition, fully articulated seats with programmable zoned heating and nine-fan cooling). Naturally, there's a navigation system and onboard Web surfing, yet the button count on the dash is slashed dramatically.
How is this possible? By cramming 700 functions onto a single rotary push knob, known as iDrive. The "i" stands for intuitive, and indeed our brief trial in a parked car revealed it to be so. Navigating the systems is easy — move the knob in any of the compass directions, and you leave one menu and jump to another. Within menus, the knob provides electromechanical force feedback — you feel detents when the knob is pointed at a menu item and the knob stops at the limits of adjustment in other menus. Press down on the knob to make a selection. Often-used radio, temperature, and fan controls keep their own knobs on the dash. We'll reserve ergonomic judgment on iDrive (and the shifter it displaces to the column) until we drive the car.
