By Jens Meiners
We are no big fans of the changeover from the 3-series to the 4-series moniker, but at least BMW is making the transition as easy as possible. The proven concept remains unchanged, and the styling is so evolutionary that a casual observer might find it difficult to tell the difference.
The 4-series Convertible
grows slightly in almost every dimension: At 182.6 inches, it is 0.7 inches longer than its predecessor; at 71.9 inches, it is 1.7 inches wider; and its wheelbase grows by 1.9 to 110.6 inches. At least it is lower - at 54.2 inches, which is 0.3 less than before. The 48 per cent front and 52 per cent rear weight distribution remains unchanged.
BMW says the open-top 4-series is "up to 44 lbs lighter" than its porky predecessor, but that isn't true of the 435i Convertible, which we drove: It comes in at a whopping 4,095 lbs, almost 100 lbs more than before - and 400 lbs more than the fixed-roof 4-series. The heavy and complex roof mechanism is a carryover unit from the 3-series and remains almost unchanged. BMW had considered switching to a fabric top, such as the Audi A5 and the Mercedes-Benz E-Class Cabriolet have, but ultimately conservative forces prevailed. At least the roof can now be opened or closed while the car is driving - up to 11 mph. You won't block the intersection if you miscalculate the red-light phase.
BMW offers two engines: The turbocharged, 240-horsepower N20 four-banger in the 428i, and the turbocharged, 300-horsepower N55 straight-six in the 435i. The former 328i's suave, naturally aspirated 3.0-liter straight-six is history, and so is the six-speed manual transmission. The 4-series Cabriolet comes with an eight-speed automatic only, which replaces the formerly used six-speed slushbox.
The 435i's direct-injected, single-turbo N55 engine matches the responsiveness of the twin-turbocharged N54 which was used for a few years in the 335i, and it is a lot more efficient: In other BMW models, this writer has experienced real-life efficiency gains of 10 per cent and more. But it is hardly a match for the sound quality of the N54, not to mention BMW's now-defunct naturally aspirated sixes. There is a sharp edge to the engine note, and the sound does not quite put BMW in a category of its own anymore. Moreover, the 435i Convertible is so heavy that it does not feel particularly fast. In fairness, the actual numbers - zero to 60 in 5.4 seconds and a top speed of 130 or 155 mph, depending on the tires - are impressive. But it just doesn't feel this fast, especially when compared to BMW's own four-door 335i. Thanks to abundant low-end torque and the busy-bee eight-speed slushbox, the 435i Convertible is reasonably quick around town and on the freeway, but this car certainly doesn't encourage racing a Boxster, or just a well-driven 3-series.
It is most comfortable on the boulevard, especially when fitted with the Luxury package - like our test car. There is noticeably more body flex than in the fixed-roof 435i Coupe, and this couldn't be any different, given its open-top design. The steering is reasonably precise, but it still lacks the wonderfully balanced weight and feedback of the old hydraulic system. So it is best to keep a reasonable pace, lower the top, and enjoy the comfortable seats and the well-equipped interior. We especially liked the ash grain wood trim with metal inlays and the functional instrumentation. The front seats are firm and comfortable, and the rear seats offer enough room for extended outings.
But there is shadow as well: This writer is not keen on certain BMW peculiarities such as the cumbersome gear selector, or the need to acknowledge input errors through the tap of the iDrive controller. Few situations are more irritating than pushing the wrong button on the gear selector when making a three-point turn, only to see an idiot screen pop up, which hides the rearview camera at the moment when it is most sorely needed. It would also be great if there were a way to keep the transmission from brutally slamming into "Park" when reversing with an open door and unbuckled seat belt. And while the materials look generally rich, the cost-cutting is a bit too obvious in the hard plastic part below the heating and air conditioning controls.
The 435i Convertible is offered from $54,900, although we suspect that few customers will stick to the somewhat stark basic trim. An additional $1,400 will get them a Luxury or a Sport Package; $2,600 buy the M Sport package. There is strong competition in the form of the Audi A5 and the Mercedes-Benz E-class Cabriolet, each with a distinct personality. But if you prefer a folding hard top, the new 4-series is by far the most appealing choice against the poorly aging Infiniti Q60 and Lexus IS Convertible. With enhanced looks and significantly improved efficiency, BMW's latest Convertible will keep its customers happy.