Car Reviews

Review: 2019 BMW M850i xDrive Cabriolet

The great 8 goes topless

By Lee Bailie Wheels.ca

Oct 1, 2019 8 min. read

Article was updated 4 years ago

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The original BMW 8 Series grand tourer, also known as the E31, was an expensive, low-volume car that sold poorly and failed to realize the ambition the company had for it when it launched in 1990 following a development cycle that lasted almost a decade. Just over 31,000 units were built between 1990 and 1999, and in North America it was a total flop with about 7,200 sold before BMW pulled the plug in 1997.

Now, a lot has changed between the late ‘90s, a time when BMW sold only cars, and 2019 where the company sells a pile of SUVs (seven in total), along with its traditional lineup of coupes, sedans and convertibles. Sure, the 3, 5 and 7 Series are still there but, much like its German rivals and other carmakers in the premium space, BMW is increasingly reliant on SUVs for maintaining sales growth, particularly in North America and China. Interestingly, 1999 marked not only the demise of the original 8 Series, but also the debut of BMW’s first SUV, the X5.

As for the new 8 Series (G15), sales expectations are likely not too high, especially in Canada, a place where it’s still very much a niche vehicle. Still, the new platform is going to feature coupe, convertible, 4-door grand coupé and, in 2020, M8 variants, so BMW is hoping its sexy new flagship finds a foothold in the premium grand tourer market.

Second Gen

The second-gen 8 Series was first revealed as the BMW Concept 8 in 2017, and the production car that would follow carries a design that hews closely to the concept. Built on BMW’s modular CLAR platform that underpins many of the company’s newer models, including the new 3, 5 and 7 Series sedans, and X5 and X7 SUVs.

As with many other BMWs of late, the G15 benefits from a light-weighting process that makes extensive use of aluminum and carbon fibre reinforced polymer (CFRP). Like the 5 and 7 Series, the 8 Series makes use of BMW’s Carbon Core technology that fuses carbon fibre into the chassis structure that not only reduces weight but also increases structural rigidity.

Review 2019 BMW M850i xDrive Cabriolet

The doors, hood and front firewall are aluminum, while the transmission tunnel is made of CFRP. Elsewhere, the bracing tube in the passenger compartment is crafted from magnesium, while the front axle is mostly aluminum. The rear axle, meanwhile, features lightweight steel with aluminum wheel carriers and control arms.

Heart of the beast

Powering the new 8 Series is an updated version of BMW’s venerable 4.4-litre TwinPower Turbo V8. Among the improvements made are the placement of two twin-scroll turbochargers within the V-space between the cylinder banks. Other highlights include an engine block made from a new aluminum alloy for improved strength, cylinder walls that are sprayed with a wire-arc iron coating for reduced friction loss, and reinforced, Grafal-coated pistons and reworked piston rings designed to better handle extra horsepower and torque.

Review 2019 BMW M850i xDrive Cabriolet

The engine also makes use of high precision fuel injection, along with BMW’s VALVETRONIC fully variable valve control and Double-VANOS variable camshaft timing. These technologies, combined with engine enhancements and improvements made to the turbochargers and their increased boost (2,900 to 5,076 psi), help the 4.4L V8 produce 523 horsepower between 5,500 and 6,000 rpm, and 553 lb-ft. of torque between 1,800 and 4,600 rpm.

My tester

For this review, BMW Canada loaned me a M850i xDrive Cabriolet test vehicle finished in Carbon Black Metallic with a Fiona Red Merino leather interior that’s loaded with a pile of optional equipment. Among the more notable extras are the Executive Package ($4,500), which includes ventilated seats, Bi-Colour Merino Leather Package ($1,500) and a Bowers and Wilkins Diamond Surround Sound System ($4,900).

Review 2019 BMW M850i xDrive Cabriolet


Bringing sexy back – inside and out

In a word, the M850i Cabriolet is gorgeous. Long (4,856 mm), wide (1,902 mm) and with a rather squat stance (1,345 mm high), the M850i cab embodies the lines of a classic grand tourer. The hood is long, the rear deck is relatively short, as it is with all low-slung coupes of this variety, and while trunk space is tight due to the retractable roof, it is nevertheless big enough to be useful.

BMW’s newest design direction with respect to front-end treatments have left some cold, but I think everything has been kept in good proportion here. The grille is large, but it’s not too big, and its angular Laser Light LED headlights are unmistakably BMW, especially during the day when the daytime running lights emit a recognizable quad LED signature that’s perfectly in line with the brand’s style tradition. Bottom line, the car looks great from any angle, especially with the top down. Simply put, it’s designed to turn heads and I can confirm it did just that.

Review 2019 BMW M850i xDrive Cabriolet Review 2019 BMW M850i xDrive Cabriolet

On the inside, the M850i cab benefits from BMW’s latest enhancements to its iDrive system. Two large, configurable digital screens (12.3-inch instrument cluster, 10.25-inch dash display) work hand in glove with the seventh generation of iDrive to seamlessly display relevant information on both screens, and allow the user to easily shift through an exhaustive menu system that governs everything from navigation to drive modes, apps and interior lighting settings.

What I especially like about this interior is the balance BMW has struck between the application of advanced technology and premium style. For example, my tester features a gear selector and iDrive Controller finished in a glass-like material that, in the case of the former, is also illuminated at night. An ‘8’ can be clearly seen through the gear selector, which is a very classy design touch.

Review 2019 BMW M850i xDrive Cabriolet

Another good example of the marriage of style and technology is the control pad that surrounds the iDrive Controller. While finished in glossy piano black, button placement and function are straightforward and should be familiar to anyone who’s driven a BMW in the past decade.

Other items of note in the M850i cab’s interior are the blissfully easy up and down function of the motorized roof, the sumptuously comfortable Merino leather seats, the incredible sounding Bowers & Wilkins audio system and the customizable ambient lighting.

The latter gets special mention because this level of detail gives the 8 Series a feeling of crafted luxury, which is something a buyer would appreciate. The lighting options (a few of which are featured in the attached photos), are simply beautiful in terms of colour, design and execution. I spent a lot of time trying out the 11 different colour options, and I have to say that on a warm night with the top down the cockpit of the M850i cab is simply a great place to be. The interior design team really knocked it out of the park.

On the road

Despite being a fast and powerful V8-powered car with a 3.9-second 0-100 km/h time, the M850i Cabriolet isn’t really a track car despite its gaudy numbers. Sure, the 4.4L V8 has giant gobs (553 lb-ft.) of torque and a peak that arrives at just 1,800 rpm, which is ideal for stop light getaways, but I doubt owners will avail themselves of it that often. That said, power delivery is smooth, and while the exhaust flaps are there this isn’t the greatest sounding V8 I’ve experienced.

Given its M designation, performance comes standard with the 850i Cabriolet. However, because I knew I wasn’t going to be driving my tester on a closed course, high performance wasn’t my primary preoccupation. Yes, I did mash the throttle several times to get a sense of the V8’s responsiveness and power delivery and I toggled through the drive modes (Comfort, Eco, Sport, Sport+ and Individual), to get a feel for their differences, but I wasn’t out to benchmark performance numbers.

Don’t get me wrong, the M850i cab has the bona fides to be considered trackable but I don’t think the track is its ideal home. The forthcoming M8 is built for that. Still, the M850i cab is plenty capable of conquering the cut and thrust of daily driving with ease.

Review 2019 BMW M850i xDrive Cabriolet

Review 2019 BMW M850i xDrive Cabriolet

The ride is firm and responsive across the board thanks to standard M Adaptive suspension which features very stiff springs and variable damping. Sport and Sport+ deliver greater stability and responsiveness, but a bit of a jittery ride. Regular driving is much more liveable in Comfort and Eco where tuning is dialled more for ride comfort. Shifting with the ZF 8HP autobox is almost imperceptible in Comfort and Eco but more noticeable in Sport and Sport+ where the V8’s revs build nicely before upshifting.

On the handling front, Active Steering has a variable ratio that allows for a smaller turning radius and easier manoeuvring at low speeds but weights up at speed for better turn-in precision. The xDrive AWD system is similarly adaptive in that it sends power to all wheels but is rear-biased so things can get a bit squirrelly in Sport and Sport+ with a misapplied throttle or a little too much confidence. Or both.

This is BMW’s way of having its performance cake and eating it too and it works fine in the M850i cab, but I can’t help but wonder what this car would be like as a dedicated rear-driver with a 6-speed manual like E31s of old. We’ll never know, but the curiosity lingers all the same.

Final Thoughts

It’s hard to not like the M850i cab. It exudes a level of sophistication, style and performance that few other cars can match at any price. It suffers from the usual compromises that all long-doored, space-deprived coupes and convertibles suffer from, but honestly, who buys a car like this for its practicality? Very few, I’d imagine. And I’d argue few would also grumble about the V8’s thirst for premium fuel, although I managed to hit a pretty good average in my test vehicle.

Review 2019 BMW M850i xDrive Cabriolet Review 2019 BMW M850i xDrive Cabriolet

I think if one envisions the M850i cab as a grand tourer for long-haul trips to the cottage or weekend getaways to wine country in comfort and fine style, it represents an ideal choice. And taking the long way there and back on as many two-lane, twisting roads as possible would no doubt be a good use of its performance capabilities.

But if working on lap times on the regular is the goal, I’d wait for the M8.




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