BMW literature states that the 745Li's Valvetronic V8 incorporates the first valve drive system with fully variable lift
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| The 745Li's Valvetronic V8 incorporates the first valve drive system with fully variable lift control of the intake valves; meaning the big Bimmer never has to strain to carry its weight. (Photo: Rob Rothwell, Canadian Auto Press) |
control of the intake valves to ever be featured in a passenger car. In its explanation of the technology, BMW states that without requiring a throttle butterfly, engine output is controlled entirely by the amount of air. The fully variable intake system also allows the engine to adjust perfectly to power requirements and running speeds, developing high torque at low engine speeds and high power at just about any speeds. The reality of this technology shines through during day to day driving, as well as when hill climbing or highway passing orders are issued. The big Bimmer never has to strain to carry its weight, as the tremendous low-end torque developed by the midsize Valvetronic-8 easily flings the 745Li about like a paper cup in a windstorm - albeit more controllably.
The second half of the 745's gutsy drivetrain is a smooth shifting 6-speed autobox, featuring BMW's Steptronic manual shift mode which is managed through a total of four steering wheel mounted buttons, cast from metal no less. Two buttons are situated on each side of the wheel, one mounted in front for thumb actuation and one residing on the backside for fingertip use. The
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| BMW's Steptronic manual shift mode is managed through a total of four steering wheel mounted buttons. (Photo: Rob Rothwell, Canadian Auto Press) |
rear mounts initiate an upshift, while the front mounts engage a downshift. This system works well and adds a sporty dimension to piloting the full-size 4-door. The Steptronic program is activated by clicking on a multi-function steering wheel button, which cycles through the options of conventional automatic shifting, a sport-shift setting and the Steptronic manual-mode feature. Placing the multi-mode transmission into Park, Drive or Reverse is accomplished electronically of course, via a small, column-mounted lever, also seamingly cast from solid aluminum. This is a nice touch that imparts a sense of sophistication and quality. The lever moves smoothly and accurately, very short distances to engage Drive or Reverse. Park is engaged by simply pushing the button mounted at the its end. In similar fashion the parking brake is engaged, however the button to be pushed is on the dash instead.
