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Cars Worth Noting: 2004 BMW 645 Ci

2004 BMW 645 Ci

After a 15-year hiatus, BMW is re-entering the Grand Touring (GT) segment with the 6 Series coupe and convertible. The new 6 is powered by the same 4.4L, 325 hp Valvetronic V-8 found in both the 5 and 7 Series, though this rear-drive coupe was specifically designed to be lighter and sportier than its sedan cousins.

With an all aluminum hood and doors as well as an aluminum front subframe and engine compartment, plastic front fenders and a composite deck lid, the coupe tips the scales at 3,781 lb. Designer Adrian van Hooydonk, who has taken a lot of heat for the bustle design of both the 5 and 7 Series, has hit the mark with the 6 Series coupe. The fastback roofline blends nicely into the deck lid giving the car a sleek and aerodynamic look and a Cd of 0.30.

But the 6 Series doesn’t just look good, it performs. Stand on the gas and your ears will think they’re in an American muscle car, a tribute to the throaty exhaust note. Toss it into a corner and it proves extremely stable thanks to BMW’s Active Roll Stabilization (ARS).

ARS replaces the conventional mechanical anti-roll bars with hydraulically-assisted roll bars. A lateral-acceleration sensor detects how hard the vehicle is cornering and sends the information to an ECU which processes the information and signals a valve-sensor block that determines how much hydraulic pressure to apply to the ends of the anti-roll bars. The hydraulic motor twists the roll bar ends in opposite directions, controlling body roll. The grand part of GT comes in the form of BMW’s usual upscale interior appointments and a slew of electronic gadgets including the infamous I-drive. It took two experienced journalists 20 minutes just to figure out how to turn on the radio.

At least you don’t need the radio on to go fast.