BMW M850i Convertible Review by Ken Rockwell

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Introduction top

This BMW /// M850ix Convertible the first car I've bought for myself since I got my 1997 Mercedes SL500 decades ago. My neighbors have numerous Ferraris, Mercedes, McLarens, Porsches, Bentleys, Rolls-Royces, Lamborghinis and more, and nothing has caught my interest to replace my SL500 for all these years — until I drove this BMW. It's that amazing. I greatly prefer my M850ix to the foolish M8 version.

We all have our preferences. Mine is for big, roomy, comfortable, quiet, practical, silent, nimble and insanely powerful convertibles that are a hoot to drive. I love comfort, agility and silent power, and the BMW /// M850ix Convertible has menu options to make the engine extra-quiet as I prefer, as well as the loud options that let it burble and scream and backfire in any mode you like. Whatever you want, the M850 does it.

I saw this on a BMW lot while looking for something else, immediately loved it, took it for a spin, and was hooked. The more I drove and investigated it, the more I had to have it.

Get the right options, and it even drives itself in traffic, which is exactly where you don't want to do the driving. The BMW's autopilot, called the ZDY Driving Assistance Pro Package (which is in addition to the regular ZDA Driving Assistance Package) lets you let go of the wheel and pedals and let your BMW drive itself for as long as there's traffic. You can raise both arms straight up in the air to wave to the Tesla drivers stuck in their sedans, whose phony "self-drive" modes require they keep their hands on the wheel. This BMW works completely hands-free.

If your garage is at a weird angle at the side of your house down a long, narrow, twisty driveway that's a pain to back down, BMW's "backup assistant" magically self-drives itself back out of wherever you parked it. Even if it's days later, it quickly can back itself out into the street where it used to take me forever trying to make 6-point turns to flip around and go out forwards.

New for BMW intro top

New since my 1997 SL500 intro top

30-year newer design: the R129 SL500 debuted in Europe in 1989 while this M850i came out in 2019.

Much more roomy interior for tall drivers. I'm only 6' 0" (182 cm) tall, but unlike other Mercedes, even with the driver's seat all the way back I barely had enough legroom, and my size 14 shoes would catch on the bottom of the dashboard in my 1997 SL500. Weird, seeing how the SL500 was always the car for ultra-rich sports stars, but now the BMW /// M850ix Convertible has more than enough legroom and footroom for guys much bigger than I.

Stability control (ESP was optional on the 1997 SL500 and not standard until later years).

Rear quarter windows allow much better rearward side visibility (behind 9 o'clock and 3 o'clock) with the top up for lane changes.

Neck & ear warmer, heated center console, door panel armrests and steering wheel.

Self driving and numerous OOPS! safety features like lane departure corrections, blind-spot warnings and front-collision self-braking.

Good intro top

An absolute hoot to drive: powerful, responsive, nimble, tight and precise with flat cornering.

Super comfortable, smooth and quiet. My M850i is a floating palace of luxury — or a floating island with its top down. This is a step above BMW's top 7-series, and I find it far more comfortable than our 2022 Mercedes S580.

Standard Adaptive M Suspension Pro (2VW) keeps cornering flat and the ride super comfy.

Impeccable interior quality, much better than my plasticy 2022 Mercedes S580. While both have all-leather interiors, my BMW /// M850i has solid alloy interior door handles while my S580 is all crappy silver-painted plastic.

Brilliantly responsive transmission. Even in COMFORT mode it immediately knows when you want to move and downshifts instantly.

BMW's X-Drive all-wheel drive system, same as Audi's Quattro, Porsche's "4" and Mercedes' 4MATIC, gives the traction to get all this power to real-world roads. Two-wheel-drive supercars like Corvettes, Cobras, Hellcats and Mustang GT500s can't get all that power to the road in their lower gears for lack of traction. For instance, the 662 hp Mustang GT500, which weighs 700 pounds less than this 523 hp /// M850i, takes the same 3.5s to get from 0 to 60 MPH with only rear-wheel drive. It all comes down to the fact that you can't use more than about 300 hp per axle on real-world roads — but rear-wheel drive car makers won't tell you that!

The /// M850ix is faster than the exotic Ford GT40 and about as fast as the new 2005-2006 Ford GT supercar. Even though the Ford GTs weigh less, they are limited by having only rear wheel drive and no way to get all their power to the road at legal speeds. While car makers try to impress us with horsepower, the limiting factor has always been getting traction at legal speeds with this much power— as every drag racer knows.

Standard 3º rear-wheel steering give a tight 39.0' (11.9 m) turning circle. Heck, this was only available as an option our $185,000 Porsche Panamera Turbo, geeze!

Very quiet with the insulated soft top: 62 dBA at 72 MPH on an asphalt freeway. This is the same as a typical hard-top car!

Great visibility even with the top up. There's nothing blocking your view to the back left when you change lanes (Regular cars have a big blind spot because of their fat B-pillars behind the driver's door).

Better handling than the coupe and four-door versions because of a much lower center-of-gravity. BMW's press data points out this convertible is 98% as stiff as the other versions, and it has no weight up high with the top down and has extra weight underneath from body reinforcements. A retracted convertible top weighs a lot less than an M8's carbon-fibre fiasco of a roof, and the extra weight at the bottom does even more to lower the center of gravity.

It's low to the ground, just like Formula One or a go kart. It's not your grandfather's sedan like an M3 or M5.

Conventional torque-converter automatic transmission means super-smooth shifting and starting from stops. The 1st to 2nd gear shift is especially smooth, unlike the PDK transmission in our Panamera Turbo.

Everything that looks like leather is leather. The center console, dashboard and doors are all covered in leather, not plastic.

"Backup Assistant" actually works fast to make it easy to back out of anything you may have gotten yourself into for parking.

The 360º Surround View w/3D View "Eye of God" camera system (option code ZX3 as part of the ZDA Driving Assistance Package) presents a stable point of view as you maneuver. This is far superior to the foolish Mercedes Surround View system in my 2022 Mercedes S580 which constantly tries to impress by moving the camera's point of view as you're trying to park, making it nearly impossible to figure out what's going on as you're also moving. The BMW system works much better to let us see where we are.

The front turn signals are separate from the daytime running lights. The signals light in amber separately from the daytime running lights, which stay white as you signal.

His and her two-fan HVAC system; each seat has separate fan speed and climate controls.

Additional master window control switch that raises and lowers ALL windows at once, a must-have for convertibles.

Biggest trunk I've seen in a convertible: 12 cubic feet with the top up! It runs all the way forwards to the backs of the folding rear seats; there's no gas tank in the way.

Retracted soft top never restricts access to the trunk. My top is always down so I can't use a hard-top convertible like the 2003-2021 Mercedes SLs, whose hard tops retract into covering their trunks! Those idiotic hard-top designs were for people who lived in Michigan or Stuttgart where they only get top-down weather a few weeks a year. (With the top up you can move up a partition and get even more space.)

Hands-free self-driving options (order both ZDY and ZDA) work great, and in freeway traffic really do drive the car all by itself.

Head-up display (HUD) works great from pitch-black darkness to driving directly into blinding sun. Bravo!

Active cruise control works great, coming to full stops and automatically stopping and starting the engine as needed when things start to move again. It doesn't time-out while stopped as Mercedes does. Active cruise control is easy to set to leave plenty of following distance; better than Mercedes which usually tries to follow too closely.

Active cruise control easily sees motorcycles and bicyclists, and if there's a narrow road, correctly locks-on to the cyclist and follows safely behind him.

Optional Neck & Ear Warmers (4NH) blow warm air from the headrests to keep your ears warm on cold nights. Mercedes calls their version AIR SCARF.

With all the heating options I find it comfy to drive, top down, at 40º F (5º C) if I'm wearing a light jacket. If you stick your arm up or out into the cold air you'll appreciate how well the M850i keeps you warm when you feel how it's freezing outside!

Standard adaptive LED and LASER headlights (4AZ, and yes, there's a yellow LASER warning sticker inside them) that shine 600 yards (600 m) on high beam at higher speeds. BMWs have always had magnificent headlights, and these adaptive beauties work wonders at night steering themselves.

All the electronics are super-smart and intuitive, making my 2022 Mercedes S580 feel like the ergonomic turd it is. There are too many ways in which this BMW betters my S-klasse to list. Among them are that the power windows and seats just work when you get in without having to turn on the car, high-beam control responds as soon as you touch the lever in the BMW while it doesn't respond until you release the lever in the 2022 Mercedes, the seat memories finish moving the seat all by itself without having to hold the button the whole time as in most Mercedes, and that if you're using the engine auto stop/start function that the BMW's camera sees when the guy in front of you starts to move and restarts the engine all by itself. We never know where to find settings in the S580 because there is no single HOME button to get to anything in a logical way, while this BMW, like an iPhone, has one main HOME screen for everything from which it's trivially easy to get to any setting. Heck, our new Mercedes clocks don't even have leading-zero suppression, a 1970s innovation that let digital clocks read correctly as 8:30 AM rather than 08:30 AM in the Mercedes The BMW remembers my seat heater and cooler settings when I get back in, while after every stop I have to turn these all back on in my Mercedes. The BMW even lets me set it to turn on seat heating or cooling - and to what level - anytime it gets hotter or cooler outside than my preset values (these are called "rules" in iDrive).

Easy to set to unlock when you get close, and lock automatically when you walk away. Far better than Mercedes KEYLESS GO, the doors are already unlocked before you touch the door handle, and you never have to touch anything to lock the doors when you leave.

Real door handles that work, not the motorized electronic ones that rarely pop out correctly on our Mercedes S580 and the new SL series.

Auto dimming center and driver's rear-view mirrors at night (passenger's mirror doesn't dim).

The i-Drive 7 system of the /// M850i is super intuitive, with one HOME button from which we can find everything we need, far better than the newer i-Drive 8 which no longer has just one HOME button making it nearly impossible to find anything again.

The /// M850i is loaded with dedicated buttons and controls for presets, climate controls and more.

Eight dashboard preset buttons are far more than just radio presets: they're easy to program to display or control anything in the i-Drive menu system like CarPlay, tire pressures, turbo boost, oil temperature, weather forecasts, trip computers, audio equalizers, gas station prices, news and more. You can see how they're programmed simply by holding your finger over each, or press a few seconds to program them. Easy! (BMW is economizing in the newer i-Drive 8 system in lesser BMWs which removes the climate controls and preset buttons and instead hides them inside a touchscreen menu where you no longer can set them by feel as you drive.)

Option ZGC are floating wheel center caps (also available at Amazon and called nabenabdeckung feststehend in German) that rotate to keep the BMW wheel logos vertical while driving or parked, just like on Rolls-Royce, who are also owned by BMW. This is super handy when you use your car as a model so you never have to rotate the logos later in Photoshop.

Voice assistant works well, much better than in our 2022 Mercedes S580. She has an option to keep her replies short, far better than the run-on baloney our 2022 Mercedes S580 "Hey Mercedes" lady gives us.

Easy to program the Voice Assistant to reply to anything, like Christine, Dorothea, Heidi, Liebchen, Schatzi or anything, and you don't need to preface it with a rude "hey" unless you want to. Even if you program it to something whacky, it still also responds to "Hey BMW."

Voice assistant works even more easily by tapping her button on the steering wheel, and she shuts up immediately if you tap that button again.

Easy to get SPORT transmission mode: just click the shifter to the left, and if you forget to put it back to regular when you park, the M850 does it for you:

BMW /// M850 Automatic Transmission Selector Returns to Standard Position from SPORT. Play video.

If you forget to turn off the automatic wipers when you get home, no worry: they won't run until the windshield gets wet again.

Audio volume control has a huge range, making it easy to set a comfortable level from ultra loud to very quiet with the engine off.

Two 12 volt batteries: a huge 105 Ah Varta AGM main battery in the trunk which runs everything, and a small 60 Ah Varta AGM dedicated to engine starting mounted on the right firewall of the engine compartment. That's 2 kWh of batteries! Only the main battery runs down if you leave the lights or radio on; the small battery is reserved for engine starting only so always can start the engine even if the main battery is dead.

Goes great over speed bumps and humps. Many cars get flustered, while the /// M850 just rolls over them.

Integrated garage door opener has a huge range of about 150 feet (50 meters) so there's no waiting for your door to open.

Integrated garage door opener needs just one tap to open the door; you don't need to hold it a few seconds as older openers did to work with modern rolling-code systems.

Bad intro top

I'm sure I'll eventually find something, but this car is even less expensive than its alternatives. The Porsche Panamera Turbo has similar power, technology and handling, but doesn't come as a convertible, lacks comfort and advanced creature features and costs 50% more. I got this BMW used and paid the same as other people pay for boring used SUVs. I wanted to get excited about the current Mercedes SL series which finally returned to a soft top in 2022, but costs far more and has the same awful user interface and motorized door handles that rarely work from our S580. No wonder I see loads of new leftover 2022 SL55s and SL63s sitting unsold on Mercedes lots in 2023, but haven't seen an M850 convertible new or used sitting on a lot in years. I got my BMW after an unheard of five straight months of rain and overcast in San Diego in early 2023 when no one else was crazy enough to buy a convertible!

The tachometer runs backwards and it isn't particularly visible, or is replaced by an MPG gauge in ECO PRO mode. The artists had their way here so there's loads of style but not much visibility to the speedometer and tachometer. Everything about the car, from the grill to the gauges to the door pulls share the same hexagonal motif, but the gauge needles are short and the same orange color as everything else. Sadly the needles aren't big, bold fluorescent VDO red, but short little orange things. Redline is 6,500 RPM and shows correctly on the HUD with 6,000 to 6,499 RPM in yellow, but 6,000 RPM is red, not yellow e on the dash tachometer. BMW does it this way for some odd reason on other similar models and reserving the correct yellow lines for the crappy-riding M8. Heck, even my 1990s Dodge Caravan company cars had much better gauges!

No cruise control stalk like Porsches and real Mercedes. Instead there are random buttons on the steering wheel that do different things depending on what the cruise control is doing (like the RESUME/CANCEL button), so you often have to hit a button more than once to get it to do what you want it to do. In Mercedes the stalks do the same thing any time you hit them. Worse, depending on what cruise and self-driving options your particular BMW has, there will be different functions in different locations so if you have more than one BMW (or get loan cars during service appointments) you'll always be hitting the wrong buttons. Porsches and real Mercedes have all had the same cruise control stalk for many, many decades, so using it is second nature and not tarnished by confusion as it is in BMW. Heck, my 1986 Mustang GT Convertible had cruise controls on its steering wheel which seemed to have much better ergonomics than BMW today.

Every model of BMW seems to have a different kind of shifter for its automatic transmission. They have different shift patterns, different functions and differently shaped controls. If you have more than one BMW or borrow a service loaner, you'll probably be doing the wrong thing as you try to shift the way you do on your usual car. Of the three BMWs in my garage (this 2019 850i, 2020 X5M Competition and 2023 530e), all three have totally different shift controls.

Missing intro top

Massaging seats were only available as part of an uncommon executive package and only for a couple of years, not in 2019 for my M850 and not today in 2024. That's OK, as the seats support my back in such a way that simply wiggling a little bit left and right feels even better than other cars' wimpy massage features.

No cooled or heated cup holders. Cooled cupholders are the only only thing I actually miss; even massage isn't needed with these seats.

No air suspension, as often seen on ultra-luxury cars. The standard Adaptive M Suspension Professional (2VW) uses individual electronically-variable dampers with regular steel springs. It works GREAT, but this means no ride height control — and no exotic air suspension repair bills either.

Not a lot of ground clearance; be careful as you usually won't clear parking wheel stops and have to stop before you run over them.

Only one button per seat for both heating and ventilation. Tap the button and use the center touch screen to set heating and ventilation. Once selected, the button alone can be tapped to change the amount of whatever you selected on the LCD. If you selected just heating, the button has three red LEDs that work just fine, and if you selected ventilation it has three blue LEDs that work as expected, but to change from heating to ventilation (or both), you have to use the touch screen again.

While the Backup Assistant and self-driving modes are great, the "Self Parking" mode is silly. It takes far longer to let the BMW 850 to try to park for you than to do it yourself. Worse, if you can get self-parking to work, the BMW M850 does most of the steering while the 850 is stopped between going forwards and back, which tends to wear out your tires faster.

Tiny sun visors don't do much. They're tiny because the windshield is very low to give the M850 a very low slung look, but leaves very little space above your eyes to put a larger sun visor. The visor doesn't extend from its pivot and the vanity mirrors are very short to fit inside the small visors.

No rear fog light; standard in Europe and in today's USA Mercedes to make yourself visible in heavy fog. This is probably because Americans have no idea what these are and most often turn them on by accident, in which case it looks like they have their left brake light stuck on.

Doesn't display current gear selection unless you have the transmission in Sport made (the shift lever moved to the left) or Manual mode via the steering-wheel paddles or the shift gate. Otherwise the dash simply shows "D" rather than S1-S8 or M1-M8, even if you've selected a Sport driving mode. (Driving modes are different from shift modes, which are but one part of a driving mode.) In other words, it shows "D" but never D1-D8 as you'd expect.

Speedometer and tachometer graphics make them mostly illegible in most modes, with tiny "needles" trying to compete with everything else on the screen.

The only switches to control the two tiny rear window segments are on the driver's arm rest. There's no room in the back seats to give them controls for these little window sections. Few convertibles have rear-seat controls for their rear windows.

No remote way to lower the trunk divider if you left it up with the top up to carry more; you have to get out of the car and lower it manually before you can lower the top.

There's no light deep in the trunk if the divider is down and blocking the light from the other trunk lights. In other words, with the top and trunk divider down you need a flashlight to see all the way back into the very deep trunk.

While BMW implies that Spotify is included along with the price of the BMW Connect data service; it's not. All it does is let you play your own paid-for premium Spotify subscription through your car radio without needing a phone. Assuming you have a phone, this feature isn't that valuable on its own.

No seat belt presenters, so we have to reach way back to grab the seat belt after we get in. Mercedes coupes offer seat belt presenters which hand front seat occupants their belts:

Specifications

Engine (Power Unit)

Quad-cam, 32 valve direct-injected V8 with twin gas-operated intercooled turbochargers, VALVETRONIC variable valve timing and double VANOS variable camshaft timing.

The curves below imply a 6,500 RPM redline, and that's where the M850i shifts at full throttle, although my dashboard tachometer redline starts at 6,000 RPM. The small, unnumbered bargraph tachometer in the HUD seems to be yellow from 6,000 RPM to 6,500 RPM.

Maximum turbo boost (indicated): 1.25 bar (18 PSI), which makes 4.4 litres (268 CID) perform like 9.9 litres (604 CID) since 1.25 bar of boost is 2.25 times atmospheric pressure, or 67.4" (1,711 mm) Hg manifold absolute pressure.

Dimensions specs top

0.32 Cd × 23.9 sq. ft. (2.22 m²) frontal area wind resistance top up. (Convertibles have typically a 0.70 Cd with the top down.)

Capacities specs top

12.36 cu. ft (350 litres) luggage capacity, top up. Somewhat less with top down, much more with one or two rear seats folded forward.

Transmission specs top

* Electronically limited to 155 MPH, which indicates about 163 MPH on BMW's deliberately optimistic speedometers. If you defeat the electronic speed limiter it should run a true 187 MPH at 5,638 RPM in seventh gear at 523 hp (390 kW), which ought to read about 197 MPH or 316 kmph on BMW's speedometer.

Weight specs top

Wheels & Tires specs top

5 × 112mm Ø bolt pattern (same as Mercedes, Audi, VW and others. Older BMWs used 5 × 120mm Ø).

Front

Rear

Performance top

Acceleration

3.5s 0-60 MPH on the track with the engine already revved in Launch and Sport+ mode, measured with a real-time optical tracker. These are how the numbers you see in ads and magazines are measured.

5.13s 0-60 MPH as measured in the real world dead-stopped at the traffic signal from idle in Comfort mode as read from the 850's own somewhat delayed-readout digital speedometer, and corrected for BMW's over-estimating speedometer which reads about 1.5 MPH high at 60 MPH (I stopped the timer when it read 62 MPH). Seeing how the digital speedometer is probably about a second or two behind the actual speed, these match.

Braking performance top

Cornering performance top

Fuel Economy performance top

EPA numbers are with the top up, which has half the wind resistance than with the top down. Expect fewer MPG with the top down.

With the top down I average 16.5 MPG locally on side roads, and I get 29.0 MPG after hours of continuous driving at around 72 MPH with the top up on the freeway. I'll average somewhere in between these two numbers depending on the percentages of where I drive.

What's unexpected is that the MPG indication is extremely accurate and if anything underestimates by about one percent. Most cars, even our Mercedes S580, read about 10% high because, unlike odometers and speedometers that have US federal requirements for accuracy, there are no requirements for MPG gauges to read accurately. Making them read higher make people much happier and less likely to start class action suits when they discover that few cars ever meet their EPA MPG in real-world driving. For instance, we actually got money back from a class action suit against Porsche (our Porsche also had a superbly accurate MPG indicator and I never found anything usual about its fuel economy).

Cabin Noise performance top

73 dBA at 72 MPH with the top down and windows up on a concrete freeway, without the windscreen.

I measure this BMW as 7 dB quieter than my 1997 Mercedes SL500 at 72 MPH: 65 dBA in this BMW versus 72 dBA in the SL500, soft top-up on a concrete freeway.

Speedometer Calibration performance top

BMW deliberately miscalibrates its speedometers to read faster than you're going. BMW calls this "speedometer advance" as explained in BMW Technical Service Bulletin TSB 1996-620296.

This keeps BMW drivers happy while they get fewer tickets and clock what they think are faster 0-60 MPH times.

Outside Temperature Gauge performance top

Climate Control performance top

The temperature sets from 16.5 ~ 27.5° C (about 62 ~ 82º F), as well as LO and HI.

The automatic fan speed control sets in five levels, as well as OFF. This means that while Mercedes simply set to AUTO and that's it unless you revert to manual fan speed control, BMWs have five automatic levels to suit your taste which vary themselves with conditions.

Harmon/Kardon Logic 7 Surround Sound System performance top

The standard Harmon/Kardon Logic 7 Surround system sounds great to casual listeners and plays loud enough to deafen your neighbors without distortion.

BMW M850ix Convertible interior passenger door panel with Harmon Kardon audio system. bigger.

As expected, the multi-amplified system can go ear-splittingly loud without effort or distortion. It easily can crank out so much undistorted bass that you can't see the view in the rear-view mirror because it's vibrating so much along with the windshield!

Stereo subwoofers. Bass is in natural stereo, not summed to mono, thanks to a 7" woofer under each front seat. It has no real subwoofers that go down to 16 Hz; these are just the typically boomy tuned car woofers under the seats. I said "subwoofers" as few people know the difference between a regular woofer as most cars have and a legitimate subwoofer which, by definition, must be able to reproduce loud and clean down to at least 20 Hz — which very few speakers can do and even more rarely in cars.

For serious music lovers it has the typical car stereo voicing: boosted upper midrange for false clarity and boomy bass to impress the innocent. This makes the Harmon/Kardon system super clear with strong bass for most people, but for serious listening requires turning down the 2 kHz and 5 kHz equalizer sliders and boosting 10kHz a bit, with the bass control adjusted to taste depending on the source material.

Treble: -3 clicks. On rare occasion I may change this depending on the source materiel.

These equalizer and tone control settings are the same for all sources; they don't save and recall differently by source as some Mercedes do.

Bowers & Wilkins Sound System performance top

If you're curious about the optional $3,400 Bowers & Wilkins (B&W) sound system, forget it if your definition of "good" means smooth, accurate and detailed sound. The optional Bowers & Wilkins system has nothing to do with B&W's studio monitors that I love so much, and seems to have everything to do with colored lights in the speakers.

The Bowers & Wilkins system is a little better than the Harmon/Kardon, but oddly it's more muffled than smooth, and its bass is still boomy rather than flat and tight. I originally wished I had gotten the Bowers & Wilkins system, but once I heard it I'm glad I saved $3,400.

The optional Bowers & Wilkins system isn't much smoother and it still has boomy bass which impresses the unknowing, but neither current system has any deep bass, typical for convertibles as they have no back deck for mounting speakers to use the trunk as box volume.

The Bowers & Wilkins system (like the Harmon/Kardon) doesn't seem to do anything to muffle reflections and resonance from inside the doors, so its sound is colored by the mangled sound coming back out from inside. What make Bowers & Wilkins studio monitors so good is their insane dedication to ensuring that all the sound coming from the backs of the drivers is completely absorbed inside the enclosure, while in a car this mangled sound comes back out to screw up the experience.

The metal grills for the Bowers & Wilkins system are bent to shape after they're perforated, so their surfaces are not smoothly rounded since the metal bends more where there are perforations. The thin aluminum grills of the Bowers & Wilkins system are easily dented which often makes them not very appealing. The standard Harmon Kardon speaker grills seem woven and are far more resistant to showing defects.

The optional DSP sound system back in my 2003 540i was was much better than either of these: smooth and detailed with tight, well-defined bass and very little resonance or stored energy.

Sound quality has nothing to do with how many watts or speakers or amplifiers a system has; it has everything to do with how well it was designed and how well the speakers are enclosed so you're not hearing sound from the backs of the speakers coming back out after it's been mangled inside the door panels. Either system easily plays loud enough to damage everyone's hearing permanently.

User Profiles & BMW ID performance top

I had a loan car and loaded my settings from my existing BMW ID into the new car.

The good news is that some settings, like my preferences for units of measurement and my various HOME screen settings came over from my main car, but the bad news is that most settings, like my settings for the numbered preset buttons, didn't. It's better than nothing, but far from perfect.

Completely Automatic Locking & Unlocking performance top

A step above anything from Porsche or Mercedes, it's easy to program the BMW to unlock automatically as I come up to it, and to lock automatically when I walk away — never having to touch any handles! Of course I have to grab the handle to open the door; the point is that it's already unlocked so I don't have to wait for it to unlock before pulling.

This also will unlock and fold out the mirrors, and then lock and fold them back in every time you walk past this car in your garage for whatever reason.

After several days of this if I don't drive this BMW that it will ignore me. I don't know if it's programmed to stop this after a certain period of time if no one gets in, or if it stops doing this if I've drained my battery a certain amount.

Parking Beeps performance top

Compared top

The Three Body Styles: Convertible, 2-door & 4-door compared top

Today's 8 series comes in convertible as seen here, or as a very similar two-door coupe with the same length and same tiny rear seats, and also as a longer-wheelbase four-door Gran Coupe with much more rear legroom and overall length.

This is wonderful, as you have the same magnificent car available in three very different body styles. The similar Porsche Panamera Turbo only comes as a four door.

The Three Performance Variations: 840i, /// M850i and /// M8 compared top

God bless BMW as each of the three body styles also comes in three different versions: a competent, powerful and economical turbo straight-six 840i, my favorite comfy and quiet BiTurbo V8 M850i, and a showy M8 which has almost the same BiTurbo V8 engine and about the same performance as the M850i but plays tricks with gear ratios, a stiff suspension and lots of engine noise and vibration with a crummy ride, noisy brakes and abysmal fuel economy to give an impression of more power.

The M8 comes in two versions, the regular M8 and the even more expensive M8 Competition.

Versus the 2019-2024 840i compared top

Today's 840i has a turbo in-line 6 that puts out more power and more torque than the 12-cylinder 5.0 litre 850i (1990-1991) or 12-cylinder 5.4 litre 850Ci (1992-1999) ever did. Only the 1990s 5.6 litre V-12 850CSi had a little more power than today's turbo 6.

While today's 840i has the same 155 MPH top speed limit, it accelerates faster than any classic 850, rated 4.7s 0-60 versus even the fastest 1992-1999 850CSi's 5.8s 0-60 MPH time.

The 840i is a Turbo 3.0 L inline six rated 335 hp and 369 lb-ft from 1,600 to 4,500 RPM — also a little more than the SL500's 5 Litre V8.

Compared to today's /// M850i, the 840i drives about the same. The 840i gets better fuel economy, while its engine has to work a little harder and thus makes more of a gentle hum rather than the silence of the /// M850i's V8 in normal driving.

Either of today's 840i or /// M850i have more than enough power for any reasonable driving.

This 2019-2024 /// M850i compared top

The /// M850i usually is silent, unless you set its exhaust to be noisy. It's an immensely overpowered car that keeps everything under control no matter how foolishly you drive. It's comfortable over any road, and sticks like the dickens and corners flat when punched or pushed. Even in quiet mode it goes Braaaap! around 3,000 RPM if you're giving it some gas.

The /// M850i is the same for all these years. The center console screen grew a couple of inches in later years, while everything else is the same great stuff.

Even the 2024 /// M850i thankfully keeps the superior i-Drive 7 system with 8 real preset buttons and dedicated climate control switches rather than the cost-reduced touchscreen-only interface of lesser 2024 models like the X5 with i-Drive 8.5.

Versus the 1999-2024 M8 and M8 Competition compared top

The M8 is noisier, rides crappier, has less-comfortable seats and sucks much more gas than the /// M850i, while giving about the same real-world performance.

Also avoid ordering the M8 with bucket seats, as you can't get neck warmers with them, a necessity for all-year top-down driving.

The M8 is not a luxury car. The M8 is a car designed for the track, not for comfort or luxury. If you want quiet comfort and luxury, you want the /// M850i as I do.

The M8 is a car for people who spend more time reading magazine reviews than actually driving, or who just like to "flex" that they bought the BMW with the highest profit margin (markup). No one takes these to the track, and when you do take an /// M850i or 840i to the track they also handle supremely well. Germans don't screw around.

While kids who read magazine reviews all know the M8 Competition has 617 hp versus "only" 523 hp in the /// M850i , what the magazines (who have always been in cahoots with the car makers trying to get you to spring for the M8 Competition without first trying the /// M850i) choose to forget is that each engine actually has the same power most of the time!

All three 4.4 litre V8s in the /// M850i , M8 and M8 Competition have exactly the same displacement and exactly the same 553 lb-ft of torque and therefore exactly the same horsepower from 1,800 to 4,600 RPM!!!

The only power difference is that while the /// M850i makes this torque up to 4,600 RPM and starts to fall off above that, the M8 makes this same torque up to 5,600 RPM and the M8 Competition does it up to 5,800 RPM. The only difference in performance is when you floor it and then only when the revs go above 4,600 RPM.

Horsepower ratings are peak and are only at very small RPM ranges. The /// M850i makes full power from 5,500 to 6,000 RPM, while the M8 and M8 Competition make their peak rated horsepower only at exactly 6,000 RPM.

Only in a small band between 4,600 and 5,600 or 5,800 RPM, and only at full throttle, does the M8 or M8 Competition have any more power. Otherwise the /// M850i, M8 and M8 Competition all have exactly the same power at and below 4,600 RPM, and rarely does anyone see more than 4,600 RPM anywhere other than the racetrack.

If you compare the power curves for all three engines, they are identical up to 4,600 RPM! Some day I'll make a graphic with all three superimposed on each other.

So why does the M8 and M8 Competition feel faster and suck so much more premium fuel if it has the same engine performance at all reasonable engine speeds?

Simple: the brutal suspensions of the M8s make you have to endure every bump and road imperfection, and it's far noisier with more engine exhaust note due to a less effective exhaust system, and very importantly the transmission is programed, even in the default ROAD mode, to shift later and keep the engine at higher RPMs so it feels more responsive. Click the /// M850i's shifter to the left for Sport programming and it does the same thing.

And last but not least, the biggest reason along with the noise and vibration that make the M8 and M8 Competition feel "faster" is the oldest trick in the book: BMW swapped-in a lower 3.154:1 axle in place of the /// M850i's 2.813:1 rear axle so the engine is always turning about 12% faster in the same gear.

The accelerator pedals are programmed differently in the M cars to work as if you're pressing them further than in the other cars. It doesn't make the cars any faster at full throttle; it just makes them seem faster at part throttle where everyone drives.

Yes, the M8 and M8 Competition are a little bit faster on the test track, but aren't faster in actual real-world driving. Personally I prefer my /// M850i because it's much more comfortable, runs longer between fuel stops and is still more than twice as powerful as anyone needs for any real-world driving where you're not wearing a helmet or being egged-on by car magazines to drive like an idiot. The /// M850i hits 120 MPH in under 12 seconds; do you really need any more power?

There are differences in gauges, menus and shifters in the M8s. For instance, oil temperature rather than coolant temperature is shown on the lower right. The M8 speedometer reads to 200 MPH linearly rather than to 160 MPH with optimized non-linear scales in the /// M850i and 840i.

I'm not kidding about the M8; I also own an X5 M Competition with the same 617 HP V8 as the M8. The M8 is more show and noise than actual go; people have no idea how much power the 840i and /// M850i have if they'd just step a little harder on the gas pedal. The M cars are a hoot to drive short distances, but most of this is rowdier theatrics rather than actual higher performance.

Versus the 2019-2024 840d compared top

This is an inline 6-cylinder turbodiesel for Europe. Like the 840i, it has loads of power and uses even less fuel than the 840i.

It's rated at 320 hp (235 kw) at 4,400 RPM and 500 lb-ft (680 Nm) of torque from 1,750 - 2,250 RPM with the same transmission but a 2.647 final drive ratio.

It's rated for 0-62 MPH in 5.2s, which is about 4.8s for 0-60 — also way faster than any of the V-12s from the 1990s.

Versus the Iconic 1990s 850i

The original 1990s 850i series are icons of automotive styling, a living classic wedge supercar with pop-up headlights and an ultralow Cd of 0.29.

1990-1991 850i

The 1990 850i had a mammoth 5.0 litre V-12 that made 296 hp with 332 lb-ft of torque.

0-60 was about 6.3 seconds with a 155 MPH limiter - oddly identical performance to the 1997 SL500 with a V8.

1992-1999 850Ci

The 850i was renamed to the 850Ci in 1992, with a larger 5.4 liter V-12 with 332 hp and 361 lb-ft of torque.

1992-1999 850CSi

The 850CSi had an even larger 5.6 liter V-12 with 375 hp and 406 lb-ft of torque.

1992-1999 840i

1992 also saw a stripper 840Ci with a 4.0 litre V8 with 282 hp and 295 lb-ft of torque.

In 1995 the 840i got a larger 4.4 litre V8 with the same 282 hp but 310 lb-ft of torque.

Versus the Mercedes SL500 (1990 ~ 2002) compared top

The SL500 was an instant timeless classic, among the world's most beautiful, expensive, practical and respected cars of all time.

The SL500 cost the equivalent of over a quarter-million dollars when it came out in 1990 ($110,000 in 1990 was the same as $255,600 in 2023!) and wowed the world with the first one-button automated electric soft top. No longer did we have to undo two latches on left and right before putting the top down; just hold the switch and 24 seconds later you're on the road.

The /// M850i looks pretty much like every other current BMW, while the SL500, one of Mercedes' proudest designs, has always commanded respect everywhere.

I had a like-new collectible SL500 when I drove — and bought — this /// M850i to replace it because this has almost twice the acceleration with the same comfy and silent ride, and with far sharper and faster handing, all while using a little less gas. The //// M850i also has all of today's latest safety, entertainment and convenience features. The SL500 has an optional CD changer, stability control was usually optional, and that was it.

I loved my SL500, but driving this /// M850i was like getting sucked into an alien spaceship with its other-worldly capabilities. This /// M850i has a much quieter ride with the top up, too!

I'm only six feet (181cm) tall, and the SL500 barely had enough legroom with the seat all the way back. Also my big American size-14 feet often would catch on the bottom of the SL500's dashboard, while I fit just fine in the /// M850i with room to spare.

SL500 is a thirty-year-older design. The SL500 came out in 1989 in Germany, and this /// M850i came out in 2019, so it's hard to compare. Both are immensely comfortable, quiet and fast luxury high-performance grand touring roadsters, and that's where the similarities end.

Versus the Porsche Panamera Turbo P971 compared top

My Porsche Panamera Turbo P971 has essentially the same drivetrain, handling, performance and brakes as my // M850ix Convertible, which is why I'm so glad I found the M850, because to me, having the top down is everything.

The Porsche Panamera Turbo P971 is an absolutely amazing vehicle with huge cargo capacity as well as unbeatable performance, but who cares if the top doesn't go down?

Honestly, I've owned both and they drive the same. They both have smooth BiTurbo 4.0 L (Porsche) or 4.4 L (BMW) power plants with north of 500 HP and smooth 8-speed transmissions coupled to all-wheel drive. My Porsche Panamera Turbo P971 also has rear-wheel steering, but it was an option rather than being standard with my 850. The Panamera has full-size rear seats; the Panamera is almost identical to the 4-door coupe version of the 8-series and sadly the Porsche Panamera Turbo P971 doesn't come as a 2-door coupe or convertible as does the 8 series.

The biggest difference is the PDK double-clutch transmission of the Porsche versus a torque-converter automatic in the BMW. The PDK shifts a few milliseconds faster if you're drag racing. The PDK can have a rough 1-2 shifts and otherwise the PDK is marvelously smooth. The BMW is always smooth regardless, and both drive the same otherwise. Each downshifts instantly if you need it and neither has any turbo lag.

Both are very low to the ground, making them more agile and fun to drive — but difficult for the less agile to enter and exit. These aren't rebadged sedans like an M3.

The Porsche has only wired CarPlay and no wireless charging, while the BMW is entirely wireless. Both have similar touch screens. Apparently the BMW's wireless CarPlay and wireless charging are the most important things to many people. The BMW is also far more advanced electronically, with a far superior app and GPS car-finding and remote unlocking and card-keys to replace conventional keys.

The Porsche costs a lot more, with a $183,000 sticker price versus the BMW's $126,000. I see and feel no difference in performance, handling or quality of materials. Both have his and her fan dual speed climate controls, all-leather trim, leather doors, leather dashboards, leather center consoles and everything. Both have solid-alloy inside door pulls. The Panamera Turbo has an alcantara (fake suede) headliner, while this BMW is a convertible!

This BMW is a much better buy when you trust your own honest evaluations versus than reading too many car magazines.

Versus the Ford GT40 and GT compared top

Acceleration wise, the M850i is much faster than the original 1960s GT40 supercar.

This super practical and comfy M850i is just about as fast and powerful as the 2005~2006 Ford GT supercar.

The supercharged V8 Ford GT has similar power (550 HP only at 6,500 RPM versus 523 HP from 5,500 to 6000 RPM and 500 lb-ft of torque only at 4,500 RPM versus the M850i's 523 lb-ft of torque in a huge band from 1,800 to 4,600 RPM).

	2005 Ford GT	// M850ix Convertible
Engine	Blown V8	BiTurbo V8
Horsepower	550 HP only at 6,500 RPM	523 HP from 5,500 to 6,000 RPM
Torque	500 lb-ft only at 4,500 RPM	553 lb-ft from 1,800 to 4,600 RPM
Drive	RWD	AWD
Weight	3,485 lbs.	4,643 lbs.
0-60 MPH	3.3s	3.5s
Quarter Mile	11.6s @ 128 MPH	11.9s @ 119 MPH
70-0 braking	153'	151'
Skidpad	0.98 g	0.99 g
EPA MPG	14/?/21 MPG	17/20/26 MPG

i Versus ix

All the 850s and M8s have X-Drive all wheel drive to get all that power to the road. I got lazy typing 850i rather than 850ix because M850ix is too much of a mouthfull.

Only the 840 comes as two-wheel drive, the 840i, or comes as all-wheel drive, the 840ix.

M Versus Not

All 850s and 8s are prefaced with an /// M, as in /// M850ix and /// M8. Again, I don't always type all that in the interest of brevity.

User's Guide top

Auto Unlocking

It's easy to set the M850 to unlock as you get within a few feet, and likewise to lock automatically when you walk away. That's right; you'll hear it unlock and lock all by itself. Cool.

This works great, but if you often walk past your car without taking it for a ride, the poor M850 gets excited, and if you're like me, its mirrors fold out and then back in again — again and again every time you walk by.

Worrying I'd wear out my mirrors from all the times I go out to the garage for other things, it's works just as easily if I set Auto Lock (only) and not Auto Unlock, so if I walk by it doesn't just open — and then close.

Setting Auto Lock (only) means it still unlocks and locks automatically since it also automatically unlocks as soon as you touch the door handle; just that it doesn't unlock when you just walk past.

Day-of-the-Week Display

CarPlay with iOS 17.0.3

For whatever reason, I lost CarPlay on 05 October 2023 after updating to iOS 17.0.3. Resetting and restarting and deleting and attempting to reconnect from my iPhones Settings > Bluetooth screen got me nowhere.

1.) Turn off my iPhone's Bluetooth and Wi-Fi connections in my iPhone's Control Center (swipe down from top right).

2.) I needed to run the engine at the same time I held down the radio power button for 70 seconds (exactly). The screen popped on and off a few times.

3.) I went to Apps on the BMW screen (press the APPS button on the center console), pressed OPTION on my center console controller, and selected something like "Update Apps and Software" and said OK a few times. I said it was updating, and about 15 seconds later it was done.

5.) Here's what I probably did wrong before. Instead of trying to reconnect with the iPhone at Settings > Bluetooth, the trick is to get the BMW to its pairing screen, select CarPlay, and in the iPhone, go to Settings > General > CarPlay instead of Bluetooth.

AHA! Works like a champ again. I wanted to write this trick down in case I'm stuck again and can't reach BMW support who were actually the ones who worked me through this. The trick of going to Settings > General > CarPlay instead of Settings > Bluetooth to setup probably applies to other car as well. Also at Settings > General > CarPlay > My Car you can reorganize your apps on your car's screen if you select your car on that iPhone screen and hit Customize.

Recommendations top

Get one, I did! It's the first car I've bought for myself in 20 years and love it to death. It's a 30-year-newer design than my 1997 Mercedes SL500 and has little in common other than being big, fast and comfortable.

Join the BMW CCA. Even if you don't love the magazines and club events, often dealers offer discounts on service and new- and CPO-cars that more than pay for your membership each year.

This all-content, junk-free website's biggest source of support is when you use any of these links to approved sources when you get anything, regardless of the country in which you live. Thanks for helping me help you! Ken.

Help Me Help You top

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BMW /// M850i Convertible

523 hp 4.4L BiTurbo V8, All-Wheel X‑Drive, 3.5s 0-60, 11.8s @ 119 MPH, Hands-Free Self-Driving