One of the sweetest powertrains around | This delicious power plant is paired up with an eight-speed automatic transmission.
Many people have been left wondering what BMW has been up to lately. From the heydays of producing lightweight enthusiast-oriented rear-drive sedans and coupes, BMW has now put a lot of their resources into producing a portfolio of very large four-wheeled monstrosities. Case in point: the X5 and X6. The funny thing about these two, is that with the right hardware (signified by the M badge), they can somehow defy physics and do a lot of crazy things, considering their physical size. The engineering and know-how is all still there at BMW, but they’ve gone after the more lucrative crossover utility market (BMW actually calls the X6 a Sports Activity Vehicle). There’s now an X4, presumably to fill in the large product gap between the X3 and recently-refreshed X5.
On the passenger car front, they’re still producing good sports cars – the M3 still remains one of the best cars I’ve driven all last year, and the new 2-Series does a good job paying homage to BMWs of the past, such as the E46 3-Series. The decision was made to split the 3-Series sedan and coupe into separate lines. The coupe and convertible would become the 4-Series, even though both would still share similar platforms and design. I’ve always been more of a sedan-person, but I understand why the 3-Series (and now 4-Series) coupe sold so well. The convertible version makes a lot of sense in warmer, more temperate climates, but I got a chance to see how it would fare in a typical Canadian winter. I picked up the key to an Alpine White 2015 BMW 435i Cabriolet, with xDrive all-wheel drive and the M-Performance package.
The split from the 3-Series has allowed the 4-Series to pursue a more dynamic two-door design. No longer just a two-door version of the 3-Series, the faster roofline rake leads to a smaller rear deck, which reduces the look of the rear overhang. The convertible is a little different, with a flatter rear deck and a slightly more upright profile, due to the power-folding hardtop roof. Not much else is changed between the coupe and cabriolet – at least from what you can see on the outside.
Underneath, with the lack of a fixed roof, BMW has had to significantly reinforce the chassis for two reasons: for safety – the windshield and roll bars need to be able to support the weight of the car in the event of a collision, and to retain the high-performance feel people have become accustomed to from BMW. Having a fixed roof does a lot to the rigidity and feel of a sports car – the suspension can do its job without having to deal with the torsional twisting that some lesser convertibles have to deal with. This pays dividends in ride quality and handling. The downside is all the weight gain associated with those chassis reinforcements. There is a 234kg (or 515lb) delta between comparable 435i xDrive coupes and convertibles – a significant amount. This impacts dynamic performance and fuel efficiency.
Other than the technical differences between coupe and cabriolet, the 4-Series retains the classic BMW look, complete with the front kidney grille and the adaptive headlights, similar to that of the 3-Series sedan. There’s also that cosmetic “vent” (carried over from the 4-Series Coupe) on the front fender that I’ve never really agreed with. My particular car is equipped with the M-Performance package, which gets you a different set of 19” lightweight wheels and staggered widths front to rear.
Inside, the dashboard and instrument cluster retain the classic BMW look and feel. Instead of the endless sea of black leather, plastic, and rubber, my particular car was fitted with the available Coral Red Dakota leather (not leatherette). The red on white contrast really makes the whole car pop, especially if you’ve got the hardtop hidden away in the summer. Unique to the convertible, the Executive Package adds (among other things) the air collar. Also seen on Mercedes-Benz convertibles, the Air Collar adds a heater vent just behind your neck. It acts almost like having a scarf around your neck – without it, the drafts coming in can make your neck feel a little cold. This isn’t what you’d want in a luxury convertible. Just behind the iDrive knob lives the main controller for the power retractable hard top.
Many coupes that get turned into convertibles sacrifice rear occupant legroom, to the point where the rear seats become additional storage space – and nothing more. I’m happy to report that the 4-Series cabriolet comes with perfectly serviceable rear seats. I’m 5’9” and sit fairly upright, and there’s enough space for a short trip in the second row. Do note that there are only four seatbelts in total – this is not a five-passenger vehicle.
The rear trunk storage space actually happens to be quite impressive in the 435i Cabriolet. While the roof performs a lot of acrobatics to fit into the rear trunk area, there remains a usable bin running down the centre. You could – in a pinch – fit a weekender bag into there with a little space to spare. The movable divider must be in the lowered position for the hard top to operate.
BMW has traditionally done a good job with their powertrains. I was anxious to try out BMW’s silky-smooth benchmark 3.0L inline-six gasoline engine. I’ve always had a thing for inline-sixes. Having one in my own car, I love how smooth they are, how well they deliver low-end torque, and how they sound at the upper end of the rev range. BMW takes it one step further by strapping a turbo on to supplement the torque delivery. BMW calls this TwinPower technology, and in the case of the 435i, this refers to a twin-scroll turbo with direct injection and Valvetronic variable valve lift.
The real-world result is an astonishingly good horsepower and torque curve. BMW rates this 3.0L N55 engine at 300 horsepower from 5800-6000rpm, and a round 300 lb-ft of torque from 1200-5000rpm. The torque peak arrives literally just off idle and the linear surge forward is immensely satisfying. If you don’t pay careful attention, you’d be hard pressed to tell the engine was even turbocharged. Turbo lag is simply not an issue – the engine pulls strongly up to its 6500rpm redline and sounds great doing it. The added 234kg definitely puts a damper on straight-line acceleration, though, when compared to the standard 435i Coupe.
This delicious power plant is paired up with an eight-speed automatic transmission, sourced from supplier ZF. Seen in many applications around the world, we have come to love everything about the ZF-8HP. Smooth take-off, fast shifts, and relaxed cruising capability are the headline features here. BMW’s programming keeps the engine in its sweet-spot, staying out of your way in Comfort mode, and rivalling some double-clutch gearboxes for shift speed and quality in Sport+ mode. xDrive all-wheel drive is available regardless of your engine choice. Overall, I think BMW produces the best engine and transmission combo in this class of vehicle. I like it better than the Lexus and Cadillac up-level V6s with their six-speed automatics, and more so than Audi’s supercharged V6.
BMW rates the 435i xDrive Cabriolet at 12.1L/100km in the city, 8.1L/100km on the highway, and 10.3L/100km in a combined cycle. Environment Canada has recently noted that February 2015 has been one of the coldest ever, with 23 out of 28 days being billed as “extremely cold”. That being said, I managed 12.9L/100km in mixed driving. The fuel tank will accept 60L of premium fuel.
The base BMW 435i xDrive Cabriolet starts at $69,100. You can drop about $1700 from that price if you opt for the rear-drive version. Most people would want to add the Premium package, for $4,900. This adds comfort access, rear-view camera (not available on the base car!), upgraded Harman/Kardon audio, and satellite navigation, among other things. If you want the Air Collar and heads-up display, you’ll need to step up to the Executive package, which is another $2,800 on top of the Premium package. My car also comes with the aforementioned M-Performance package, which gets you the unique wheels, but also the Adaptive M suspension and variable sport steering. All that being said, this fully-loaded 435i xDrive Cabriolet stickers at $79,200 before destination charges, additional dealer fees, and of course, taxes.
For what it’s worth, a similarly equipped Mercedes-Benz E400 Cabriolet goes for $78,000, but won’t necessarily feature the same driving dynamics. The unique draw with that vehicle is the Mercedes-Benz E550 Cabriolet, which provides turbocharged V8 power under the hood. The Infiniti Q60 convertible (as of this writing, is still based on the old G37) is also available, but its usable trunk space all but completely disappears if you have the hard top retracted. On the other hand, the Q60 convertible is still available with a six-speed manual! The common denominator with these two competitors is that both are rear-drive only. Canadians love their all-wheel drive, so BMW is capitalizing here with their xDrive all-wheel drive.
Owning a convertible sports car in Canada can be a testing experience at the worst of times. Here in Toronto, our summers are generally quite pleasant. Our winters, on the other hand, make us famous. It’s not at all impossible to live with a ragtop in the winter, but one needs to look forward to the summer to be able to justify it. Hard-top convertibles make year-round ownership a little easier, but what if it is -15 degrees Celsius outside and you want to put the top down? You won’t be able to – the main iDrive screen will give you a long list of reasons why the operation isn’t permitted (the top will not retract below -10 degrees Celsius). At the end of the week, I was only able to retract the hard top in the confines of a heated underground garage. It’s unfortunate that I couldn’t get to enjoy some quality time with the summertime sun and wind in my hair, but the rest of BMW 435i xDrive Cabriolet does a pretty good job delivering the BMW feel, regardless of the season.