From the driver's seat, the BMW 3 Series Convertible communicates its understanding and acceptance of the responsibility of living up to the brand's heritage. Unlike most of its kin, this BMW remains a car a driver puts on and wears more than climbs into. And save for a few areas where electronics numb messages the car and the driver wish to exchange, it's what people should expect a BMW to be.
Put more plainly, the 3 Series Convertible, like the 3 Series Sedan and Coupe, is a joy to drive. Step on the gas, and the car goes. Step heavily on the gas, and it flat out scoots. More rapidly, of course, in the 335i, with its twin turbos, than in the 328i. But the latter is no slouch, and is, in fact, all most everybody will ever need. Don't count on saving any money at the gas pump, however. The EPA rates the smaller engine at but one mile per gallon better than the larger engine and this only in town; on the highway, their fuel economy is about the same.
For those few who want more than they can use, there's the 335i, and for a turbocharged engine, its power delivery is decently managed. The idea is simple, really. Use a small turbocharger, which spools up relatively quickly, to get the power boost started early on at lower engine speed. Then, as that unit begins to top out, bring in a larger turbocharger that's been spooling up and hits its stride about the time the smaller one fades. This gives the best of both worlds for an atmospherically enhanced engine: decent torque at low engine speeds and more horsepower at high engine speeds. It also minimizes dreaded turbo lag throughout the power curve and, with due gratitude to the engine's electronic brain, shows a barely perceptible surge as the tachometer needle passes 4000 rpm when the larger turbo takes over. Running gear sounds making their way inside the car are muted but pleasantly mechanical. From outside, sadly, the exhaust sounds more like a hopped up Accord with a coffee can muffler than one of Germany's finest.
The Steptronic automatic gets that power to the road as effectively as the manual transmission. Not so much in stopwatch-measured quickness as in smoothness, precision and ease of use. Shifts are superbly executed, whether up or down and at partial or full throttle. Drivers intent on rowing their own can use the Steptronic to pick and hold a gear, but this is hardly necessary. The automatic's brain does a masterful job of choosing the best gear, whether it's to power out of a tight corner or to squeeze the most miles out of a tank of premium fuel on a relaxed Sunday drive.
The manual gearbox, on the other hand, feels mushy, like it's moving the gears with cables and pulleys. Perchance it's the result of cramming slots for six forward gears into a shift pattern more properly proportioned for five gears, but whatever, this is a distinct step backward from previous 3 Series manual gearboxes. Given BMW's aspirations as the premier driver's car, it also comes off poorly in comparison to the manual boxes in the VW Eos and the Volvo C70, both of which are as good, or nearly so, as the 3's; what has to be even more galling to the marque is that the six-speed manual Nissan has put in the new, sub-$30,000, '08 Altima Coupe is quantum degrees better, more like what a BMW box should be than this 3's. Overlooking the spongy touch, upshifts flow naturally from gear to gear, even if the driver skips a gear or two, a not uncommon inclination when crawling through rush hour traffic. Coming back down through the gears, drivers must take care if they wish to take a gear out of its normal sequence, as this requires some careful aiming of the shift lever to land in the desired slot.
Steering gives good feel and feedback, provided the box for the optional Active Steering has been left unchecked. This is yet another case of BMW trying to make better something that was fine the way it was. First, the basic, non-Active Steering is excellent in is own right, with sharp turn-in and good on-center feel and directional stability. And second, the Active Steering in its earliest form, that is, when it first appeared in the 5 Series a couple years ago, was a pleasant, and welcome, surprise. It waited patiently and unobtrusively until a specific occasion called on it. Now, it seems to be working all the time, as if it's hoping to guess what a driver wants and delivering it almost before the driver asks. The steering wheel moves seemingly constantly ever so slightly beneath the driver's hands, without regard to any driver input. We found this unsettling on long stretches at high speed on arrow-straight interstates and on twisty, two-lane, back roads. In each case, we had to concentrate on keeping the car going where we wanted, especially through sweeping turns, which required frequent steering adjustments to hold a desired line.
The brakes are tops, measured purely by stopping power and consistency. Here, the multitude of electronic assists and adjustments mostly bear much appreciated fruit. One complaint grows out of the system's persistent over-modulation of the pressure transmitted to the pads and discs from the brake pedal as the car nears full stop. This decidedly non-linear, progressive algorithm makes a smooth stop sans rocking dip of the front end all but impossible.
On the bright side, and there is one, the 3 Series Convertible's ride and handing remain high points of any time spent behind the wheel. The '07's wider track (distance between the tires side to side), by more than an inch in front and more than half an inch in the rear over the '06 soft top, delivers a flat, stable arc through sharp turns and long, sweeping curves alike.
The Sport Package suspension delivers a ride just this side of stiff and, given the competence of the standard suspension, is an unnecessary added cost.
Cowl shake is more fully contained than in either the Eos or the C70. The nearly equal front/rear weight balance minimizes understeer (where the car doesn't want to turn) and oversteer (where the car wants to spin out) in hard cornering. Just as important as that front/rear balance is the careful distribution of the weight between and over the front and rear wheels that keeps the car from feeling twitchy.
And there's always the Dynamic Stability Control system in the event a driver has truly flouted the laws of physics. This system's basic responsibility is to employ selective brake application and throttle adjustments to minimize chances of the car spinning out in poor weather or emergency maneuvers. Besides this, and in addition to managing the basic functions of ABS (which allows the driver to steer the car during emergency stops) and electronic brake-force distribution (which adjusts brake application front to rear for optimal stopping distance), BMW's DCS system incorporates, and activates as deemed necessary by its carefully trained electronic brain, compensation for brake fade (increasing brake line pressure as brakes heat up to maintain consistent pedal pressure characteristics), brake drying (lightly touching the pads to the discs periodically to keep the latter dry when windshield wiper use indicates wet pavement), brake standby (pre-loading the brake system when the driver abruptly lifts off the throttle, possibly indicating a sudden stop), start-off assist (keeping the brakes applied for a few seconds after the driver lets off the brake pedal for smoother starts on hills) and traction control (tempering wheel spin in slippery conditions).
Noise levels in the Convertible are low, top up or top down. Top down, front seat occupants can converse in normal tones at speeds moderately in excess of interstate posted maximums. The optional windblocker is somewhat effective, but longer hairstyles will benefit from some post-travel grooming. Top up, no surprise, it's as close to a coupe as it can be without actually being one. There's the slightest whistle from the seams between the top's elements, but the full headliner quiets almost all of the outside irritants. In this, the 3 Series Convertible tops the competitors, with better sealing around windows and a more rigid structure overall.
