In terms of driving dynamics, there's no controversy. BMW's 7 Series has been widely lauded for its outstanding performance and ride. It's hard to rave about a vehicle that drives so well. There are only so many ways you can say great," and the 7 Series does everything extremely well.The first thing we noticed about the BMW 745i was its wonderful, magic-carpet ride. This car smoothes out bumps, even speed bumps, to a point of astonishment. It's incredibly comfortable, yet the driver does not feel completely isolated from the road. The 745i senses when it's being driven hard, retuning the suspension appropriately for improved handling.
BMW's Active Roll Stabilization, a system of computer-controlled active anti-roll bars, increases roll resistance in hard cornering to keep the body flat in turns. At the same time, the system maintains enough suspension compliance to keep the tires planted on the road. Bumps in the middle of a high-speed corner do not upset the handling balance one whit. Several factors are at work here: a near-perfect weight distribution of 50 percent front and rear, which means neither end of the car is more prone to slide than the other; a highly rigid chassis that allows precise suspension tuning; and minimal unsprung weight, thanks to lightweight aluminum wheels, brake calipers and aluminum suspension components.
Remember: weighing up to 4900 pounds, depending on equipment, the 7 Series is not a small car. But in some respects it feels smaller than it is. Anti-skid technology makes adjustments to maintain handling balance whenever grip is lost to any one tire. By applying braking force to individual wheels, it almost seems to bend the laws of physics. Just steer this thing where you want to go and the 7 Series takes you there. I explored this on a fast, greasy corner over a crest that un-weighted the suspension. All four wheels lost grip, but we simply motored around the corner, drifting just slightly wide of the intended line. I never lifted my foot off the accelerator pedal nor made any adjustments in the steering. No special action on my part was needed; the 745i did all of that for me. The anti-skid system is transparent, in that you can't feel it kick in and out. BMW's system is far less obtrusive and more performance-oriented than similar systems found in Mercedes-Benz and Lexus automobiles. That means that it probably leaves the driver a bit more room for errors.
Steering the 745i is a joy. The rack-and-pinion steering is super sharp and precise. It's very light at low speeds for parking lots, but firms up at higher speeds for improved driver feel. It also steps up response by 10 percent as the wheel is turned off center, which means that the more you turn the wheel, the faster the car responds. With this steering system, it's easy to drive the 7 Series with extreme precision on winding roads at very high speeds, placing the tires exactly where you want them. When hitting bumps, there's little or no kickback to the steering.
Either of the 7 Series drivetrains is absolutely silky when cruising around. The new six-speed automatic transmission is extremely smooth, yet it's the most responsive I have ever experienced. Those are usually mutually exclusive benefits. Hit the accelerator pedal and the transmission drops a gear or two without any of that hesitation found in so many automatics. This six-speed automatic is smaller and lighter than the previous five-speed automatic. The additional gearing gives it quicker performance off the line with a lower first gear, better response in the mid range with ratios that are closer together, and improved fuel economy with taller top gears. The 745i does offer a feature allowing the driver to downshift manually using a pair of buttons on the steering wheel, but I found that feature to be superfluous. With a transmission as responsive as this one, manual shifting seems more of a toy than anything else.
The 4.4-liter V8 engine is superb. It's very smooth when cruising. Combine the smooth drive train with the smooth ride and the 745i feels deceptively slow. While rolling out of a jerkwater town in the Hill Country outside of San Antonio, I was preparing to put the accelerator pedal down to gain speed, until a glance at the speedo revealed that I was already cruising at 80 mph. This car feels happy cruising at 80 to 100 mph all day. I found myself coming into high-speed sweeping corners and low-speed tight corners carrying more speed than I initially realized, then having to get on the brakes a little harder than originally planned. It wasn't a scary thing, because the 7 Series almost never loses its composure. Just kind of a whoa, Nellie, slow this baby down. This combination of outstanding dynamics and deceptive travel speeds says something about both the joy and the trepidation in a car as capable as the 7 Series. You need to watch your speed in this car.
Punch the accelerator pedal (technically, it doesn't use a throttle) and the 745i leaps into action. BMW claims it can accelerate from 0 to 60 mph in just 5.9 seconds. The V8 is rated at 325 horsepower and 330 pounds-feet of torque, a huge increase over the previous BMW V8 and similar in output to the previous BMW V12. Yet the 745i is rated by the EPA at 18/26 mpg City/Highway, a 13-percent improvement over the previous BMW V8. Its sophisticated Valvetronic system has eliminated the throttle completely, eliminating pumping losses for improved efficiency by letting the valves, which benefit from BMW's double VANOS variable timing, control the airflow through the engine.
If that's not impressive enough for you, try the V12. The 760Li was launched in 2003 with a 6.0-liter V12 engine that shares its basic architecture and most of its technology with the V8. Yet the V12 adds an innovation of its own. With direct fuel injection (something previously reserved largely for diesel engines), BMW's V12 delivers fuel directly into the cylinders, rather than to intake ports on the cylinder head. This improves power and reduces emissions. So equipped, the 760Li generates 438 horsepower and an impressive 444 pounds-feet of torque. The V12 is turbine smooth, and whisks the sumptuously luxurious 760Li to 60 mph in 5.4 seconds, or as quickly as some Porsche 911s.
Modulating the brakes is easy, and the 7 Series can stop in a big hurry when necessary. Massive ventilated disc brakes, among the largest and most powerful BMW has ever used, are fitted with aluminum calipers at all four corners. Electronic brake proportioning ensures that the meaty tires are making best use of all available braking traction by transferring braking force to the tires with the best grip. Dynamic Brake Control reinforces the driver's pedal effort in emergency braking to help the car stop in the shortest possible stopping distance, even if the driver mistakenly relaxes pressure on the brake pedal. The Hill Hold feature will automatically hold the car at a stop until the driver presses on the accelerator pedal, and set the parking brake when the car is turned off. Hill Hold can be switched on or off using the iDrive menus."
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