BMW 645 Ci Coupe
BMW 645 Ci Coupe, A totally new BMW 6 series coupe, just a bit smaller than the new 5 series, has been launched by the German company. It bristles with new technology, including variable ratio steering, and adaptive cruise control, but as always with a new BMW the emphasis is on driving pleasure thanks to advanced technology.
Styling of the new car is in the new BMW idiom that is some nice lines mixed up with some slightly odd ones. Still, it is a brilliant car for all that, powered initially by the excellent 4.4 liter V-8, which comes with variable valve timing and lift. It is an all-aluminum unit developing 329 bhp at 6,100 rpm. Thanks to the variable valve timing, maximum torque being produced fairly low down.
Sequential Manual Gearbox (SMG)
There are three transmission options each with six speeds. In addition to the normal manual and automatic, there is BMW’s SMG Sequential Manual Gearbox. The SMG is basically a manual gearbox which has a conventional gear lever which the driver can use to push forward or backward to shift, and also a pair of paddles on the steering wheel these paddles are now becoming the way to change gear among sporty drivers.
Suspension of the 645Ci is normal BVMW with MacPherson struts at the front, and a multi-link system at the rear. All pretty conventional, except that the components are almost all made from aluminum to save weight.
BMW 645 Ci Coupe Active Steering
New to the 645Ci is active steering both the ratio and steering effort are varied to suit the situation. For example, at very low speeds, there are less than two turns lock-to-lock against three to five on cars of this size and the steering is very light. As the speed increases, so the steering becomes heavier and also less direct, giving the driver more control.
Electronics are also used to improve cornering, and prevent the wheels spinning on muddy or gravelly surfaces. This is based on ABS and traction control, but includes several systems all aimed at improving cornering speed and safety, which BMW has been improving steadily over the past 5 years with previous versions of Dynamic Stability Control (DSC). This advanced technology allows high speed cornering with safety.
And almost no roll on corners
On top of that there is Dynamic Drive similar to the system Citroen introduced in Europe some years ago, but more refined. There are front and rear active anti-roll bars instead of the normal plain steel bars. Each has a two-piece anti-roll bar with an electric motor. When going straight ahead, the two parts of the anti-roll bar are unconnected, so the ride comfort is improved. When cornering, the motors counteract body roll, which they cut by 80%.
What does it all add up to? Elegance and refinement, with very fast and flat cornering, and agile steering. Quite a car, even if it is large and not the most elegant BMW built. Not powerful enough for you? Rumor has it there's a 6 Series coupe with a V-12 engine coming.