Almost eerily silent at idle, the 645Ci's 4.4-liter V8 unleashes a deep, throaty snarl at take off.
Its six-speed manual transmission is tuned for more aggressive driving, automatically adjusting valve timing and lift as well as intake manifold length to boost output to 333 hp. The 117-lb gearbox provides 442 lb-ft of torque, maximum, making it one of the most high-powered manual gearboxes for a passenger car. Top speed is reached in fifth or sixth gear.
Drivers experienced enough to push the coupe's limits no doubt appreciate the balance between power, handling, and braking. At increased speeds active steering reduces the steering angle and power assist provides better and smoother directional control. The result: tremendous cornering power and remarkable stability. The standard issue DSC (dynamic stability control) applies slight braking on the inner rear wheel in a turn at medium to high speeds. Another manually activated feature, dynamic traction control, increases traction on the drive wheels giving the coupe a more-sporty feel. ABS and CBC ( cornering brake control) are also standard.
Inside, performance meets its match with luxury. Front and center in the driver-oriented cockpit is the iDrive computer-console. Its single, large, multifunction knob sits in the console between the front seats for easy activation of the navigation system and comfort controls. The navigation system worked great during our weekend test drive, helping us easily navigate a new route around a washed-out bridge in rural Ohio.
Matte-chrome instrument clusters and polished wood trim, along with leather seats are sure to please. The multifunction sport steering wheel is leatherwrapped and features power tilt/ telescopic adjustments. It's also equipped with audio and BMW cellular-phone system controls. In the back, a tall center cushion separates a pair of body-contoured bucket seats with enough room for adults, but not for long drives.
The standard eight-speaker sound system has two central woofers housed in the side sills a patented BMW concept that reportedly improves bass sound throughout the entire car. Other nifty features we liked were the coupe's head and taillights. Adaptive headlights swivel as they follow the course of the road, reportedly giving 90% more illumination than conventional lights. High and low-beam control units are fed data regarding steering angle, yaw rate, and speed, and an electric motor moves the lights left or right accordingly. The LED rear lights incorporate brake force display enlarging the brake light area when the brakes are applied hard to provide additional warning for those following behind.
Optional equipment boosts the price of our tester from its $70,000 base to nearly $76,000.