Released in 1976, Aerosmith’s fourth album, Rocks, is considered by my counterparts in music journalism to be the band’s rawest and most influential. The same year, BMW was replacing its company-saving Neue Klasse cars with the first-generation 3 and 6 Series coupes, each a major follow-up and wildly influential in its own right. By 1984, BMW was releasing its third M car, the M635CSi, as the original Aerosmith lineup reunited for the Back in the Saddle tour, named for the first track from their last successful album, Rocks.
In 1989, the 6 Series was replaced by the 8 Series. Nearly 30 years later, the 6 Series is once again on the cusp of being replaced by a more advanced, higher-performance, more luxurious 8 Series. Aerosmith, incidentally, is on an extended farewell tour.
I share the opinion of many of my contemporaries that BMW was at its best back then, when it told the customer what a German luxury sports car was rather than listening to focus groups whining about cupholders. BMW, and the M division in particular, had a clear sense of identity, one that seemed to wander in the 2000s. No more. The M5 is “hair-on-fire great” once more, per our review, and a prototype of the upcoming 2019 BMW M850i xDrive Coupe I’ve just driven provides definitive proof M division has its mojo back.
The return to form and change in philosophy go hand in hand. Speaking with M engineers as they performed final calibration tests on the heavenly roads of North Wales, it was clear they’d been given a long leash and used it to build the car they wanted, not anyone else’s idea of what an M ought to be.
To wit, the car comes in one mechanical spec: 4.4-liter V-8 making 530 hp and 553 lb-ft, ZF eight-speed automatic, rear-biased all-wheel drive, electronically controlled differential, rear steering, continuously variable dampers, and 20-inch wheels shod in purpose-made Bridgestone Potenza S007 summer tires staggered 245 front and 275 rear. The only performance option: electrically actuated active anti-roll bars.
The prototypes, naturally, had the active anti-roll bars fitted to the control arm front and multilink rear suspensions. Just as the all-wheel-drive system varies the torque sent front and rear and the dampers vary the compression and rebound at each wheel, the anti-roll bars adjust their resistance front and rear independently of each other to maximize stability in every condition. Unlike other applications, though, they also pre-tension a split second before you turn based on a finely tuned steering wheel sensor.
The result, in auto reviewing parlance, is an executive coupe that shrinks around you. Make no mistake, it’s a very large car, but it doesn’t drive like one. No, it drives like a much smaller, nimbler car than you’d dare hope just looking at it. Precision was the word the engineers used to describe their objective, and it shows. On narrow, cold, wet roads I’d never seen before, I felt immediately comfortable driving quickly, and I was fully confident in putting the wheels precisely where I wanted them at every moment. There’s no higher mark of a sports car.
A major factor in this behavior is weight. The engineers wouldn’t get more specific than to say it’ll weigh less than the 6 Series, which as configured would mean less than 4,400 pounds on the high end. The 8 Series Coupe benefits from a mostly aluminum body, carbon-fiber roof and transmission tunnel, composite trunklid, and the latest in high-strength steel alloys and stampings, which in some places are lighter than the 7 Series’ structural carbon-fiber parts. The cumulative effect is a car that feels absolutely solid, as if made from stone, but not heavy or ponderous.
The M team has also added lightness to the steering, and it’s a welcome reversion. For too long, some automakers have equated heavy steering with sportiness, but engineers with M have rightly realized lighter steering is more precise. What’s more, despite the presence of both electric power steering and all-wheel drive, there’s real road feedback in it, the most I’ve felt in a big BMW in years. I drove over every bump I could find just to make sure I wasn’t imagining it.
Unlike many a press preview, bumps there were. The engineers were on hand to make the final tweaks to the suspension, and it needs to work right on all surfaces. It was relieving to find they’ve little work left to do. The springs are clearly stiff, and they push the wheels down firmly against any bump and into any hole, but the worst you could say about it is the wheels feel heavy. The adaptive dampers do a master’s work of isolating impacts and softening the blow. The car rides appropriately stiffly for a sports car but without any harshness or brittleness. Refusing to mount run-flat tires was the right call.
Appropriately, the shocks stay with you in bumpy corners. All too often we find cars that ride and handle well on a racetrack but can’t deal with cracked or lumpy pavement midcorner on a road. No such problem here. Those bumps don’t upset the chassis at all. You feel them, but it’s an acknowledgement, not a reaction.
What’s more, dialing up Sport and Sport Plus modes doesn’t correspond to increased punishment. The biggest difference is in the reduction of head toss, which nearly disappears. Unlike some cars, you don’t have to put it in Comfort the moment you turn off the back road. The car exhibits very little body roll to begin with, and the performance modes simply magnify the body control.
The real wizardry, though, is in the coordination of all the variable bits. Just counting them all could give you a headache. Yet through endless refinement, the variable dampers, power steering, torque-vectoring all-wheel drive, rear steering, active anti-roll bars, and active differential all work together seamlessly. You can’t pick out when the rear anti-roll car is stiffer than the front or when the rear steering changes phases or when the differential locks up. At most, you can feel the front end help pull you out of a corner, but only after the rear end has dug in first. Indeed, the only time the car feels all-wheel drive and not rear-wheel drive is when you’re rolling hard into the throttle exiting a corner. At lighter throttle in the same corner, you might not even notice it.
Does it ever put down power, though. As if to drive home the rear bias, the car gladly spins the inside rear tire half a rotation when making an assertive exit from a parking lot, but from then on, it’s all about grip. Entering a corner, the front end responds immediately and the body steels itself to the g’s. There’s equally little dive under braking or squat under acceleration as there is pitch or yaw as you change directions. Getting back into the throttle is rewarded by assistance from the front wheels clawing you out of the corner.
Despite the car’s weight, the cool weather, and the dampness of the road, the Bridgestones never lost their bite, so I couldn’t tell you from first-hand experience whether it tends toward oversteer or understeer. The engineers tell me it drifts nicely, though.
It certainly has the power to be a drifter. The updated engine employs new intake and exhaust systems, larger twin-scroll turbos, and new metallurgies in the pistons and cylinder walls to reduce friction, and it runs significantly higher fuel pressure to its direct injectors with the help of a second fuel pump. Accordingly, power increases by 85 hp and torque by 73 lb-ft. More important to the driver, peak torque arrives slightly earlier and is maintained slightly longer. In practice, once you’re moving, the engine speed almost never drops below the peak torque window, effectively eliminating noticeable turbo lag.
Fixing any momentary torque deficiency is an updated transmission with shorter first through third gears for performance and quicker shifts (as well as longer sixth through eighth gears for fuel economy). I was only able to catch the prototype out of step once, and even then the result was only a slightly lumpy gear change. Otherwise, it shifts as smoothly and perceptibly quick as a dual-clutch.
The result of this teamwork is a car that always seems to be in the right gear and is always ready to respond forcefully. Power is delivered in an urgent surge no matter the engine speed at the time of the request. Horsepower peaks from 5,500 to 6,000 rpm, just shy of redline, and comes on with a smoothness and linearity that makes the car deceptively quick. That is to say it doesn’t feel quick until you’re really hauling.
When you do request the engine’s full attention, you’re rewarded by a dual-mode exhaust system that emits a bass-heavy howl. Unlike a Mercedes-AMG turbo V-8, it’s not a monotone burp at all engine speeds but actually engages the higher frequencies of a naturally aspirated V-8 as you approach redline. It’s not the old M3 engine, but there’s a hint of it in the chorus.
That’s just for starters. Cycle the Sport button until you get Sport Plus mode, and the powertrain’s entire demeanor changes. Revs are kept high, never dropping below 4,000 rpm until you’re coming to a stop. The transmission downshifts as quickly and through as many gears as possible under braking to keep you high on the horsepower curve. Crucially, the shifts don’t get needlessly hard, and the throttle calibration only sharpens slightly. Again the car demonstrates its commitment to precision over feeling sporty to the uninitiated. The transmission easily meets the benchmark of the Porsche PDK, giving me no reason to ever use the shift paddles. It behaves exactly as I would were I shifting myself.
The one system where I found room for improvement was the braking, and then only in the pedal feel. The brakes themselves are monstrous and indefatigable, exhibiting no signs of fade during prolonged hard use. The initial bite is appropriately sharp for an M car, and the feedback is good up through moderate hard braking. It’s when you’re really deep into the brake pedal approaching a sharp corner that it could use more feedback. At this point, it feels about the same as it does under moderate braking, giving you no additional tactile indication of how close you are to ABS intervention and the limits of the brakes. The engineers seemed to appreciate the feedback, and I hope they’ll agree and address it in the final product.
It would be remiss to point out this prototype isn’t a full-blown M car, either. Unlike with the previous-generation 8 Series, we expect this version to get a proper M8 variant down the road. In the meantime, though, the M850i xDrive will receive a track package with improved cooling and other as yet unspecified modifications. Yes, they really do expect people to track this car and enjoy it. “99 percent of drivers can’t get a better lap time out of a 911 than this car,” one engineer told me. At the same time, he stressed the point of the car is the driving experience, not lap times.
Despite all that, it will also offer all of the advanced driver-assistance features of the 7 Series, such as adaptive cruise control and lane keeping assistance. The M people consider this model’s closest competitors to be the AMG GT and Porsche 911 variants, but they are quick to argue those cars have narrower bandwidths even in their most luxurious trims. One could make arguments for the S 63 Coupe or the R8, but the former isn’t nearly as sharp, and the latter is a supercar, not a GT car.
Do these latest big bruisers, the M5 and M850i, mark the second coming of M? They certainly give every indication of it, but two data points do not make a trend. I can confidently say, though, the M engineers are back in the saddle and the division is all the better for it. After all, “Back in the Saddle” was as much about sex as it was cowboys in the Wild West, and these German cowboys have made themselves a steed that’s as good a ride as any.
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