SWEET CRUISER; BMW ups the horsepower- and the fun-in the 650i.(News)

Byline: ROGER HART

When readers were polled last year for our BMW 645Ci AutoFile ("Six Machine,'' Dec. 19, 2005), owners said the coupe has the best execution yet of the notchy design element called the "Bangle butt,'' unceremoniously named in honor of BMW chief designer Chris Bangle. A good number of AutoWeek editors agree the 6 Series has killer looks.

After a recent stint in BMW's latest 6 Series, the 650i convertible (no C designation for this model), we ran an unscientific poll of those same editors, and they agree the car's presence is significant whether in the soft- or hard-top form. The 650i looks great, even with the fabric top neatly folded in the trunk.

But looks aren't everything. Luckily the 650i has a great personality, too, with nothing to be ashamed of when it comes to performance. BMW increased the V8's displacement from 4.4 to 4.8 liters, with output jumping from 325 to 360 hp, and from 330 to 360 lb-ft of torque.

The performance is so good that one staffer says, "It isn't the 500-hp V10 in the M5 and M6, but this is a damn fine V8 nonetheless. There is power aplenty and it gets to the ground smoothly and with no fuss.'' Another notes, "Not once did I see a space in traffic or a merge I couldn't get to due to lack of oomph. Frankly this car hauls Bangle butt.'' The V8 coupled with the smooth-shifting six-speed manual is a joy to operate.

We experienced the 650i in part on a long drive to the Wisconsin heartland. The car is amazingly quiet with the top up, something not all convertibles can claim. The thick, insulated top does a nice job isolating the cabin from road noise-or a heavy rain. With the top down, wind buffeting is minimal and you can easily carry on conversations with the front-seat passenger. Speaking of seats, the sport seats in our tester were superb, with excellent side bolstering.

While some editors harp on the ease of use of iDrive ("I counted nine distinct jogs, taps and turns of the wheel to get from the navigation screen to making a bass-tone adjustment on the radio!''), the top's operation is ...