Porsche 911 Turbo S vs BMW M8 Competition twin test

Published: 19 June 2020

► Porsche 911 Turbo vs BMW M8
► Turbo giants slug it out
► Full CAR magazine twin test 

What the coffee couldn’t manage, the M8 Competition’s V8 is doing effortlessly. Just a few moments ago, as I slid aboard the 2+2 BMW coupe, my brain was still on the pillow; still on standby, with only essential systems online. Now, thanks to the BMW’s awesome V8, I’m very much awake. This is one ferociously quick car. 

We’re snaking though wild hill county, the bone-grey road the only conspicuously man-made scar on a landscape that was here long before us – and will go on long after we’re gone. There is no other traffic; the only other living souls are sullen birds that take flight as our two-car cacophony heads their way.

Join the CAR newsletter for in-depth reviews, news and analysis

The S63 engine up front (shared with the F90 M5) is an upgraded version of the 4.4-litre V8 found in the M850i. In the full-blown M car you get more rigid engine mounts, upgraded lubrication and cooling, and a high-pressure fuel-injection system. The net result is 616bhp and 513lb ft of torque, all faithfully translated from fast-spinning crankshaft to a faintly absurd rate of forward motion that doesn’t so much get your attention as grasp it with both hands and fix it with a maniacal stare.

Where the road straightens out, blitzing between forests and running next to fast-flowing rivers, the BMW piles on speed like a dive-bombing hawk. Even when you’re waiting for it to struggle, such as when you ask it to haul what isn’t a light car, uphill, from a tight corner, the V8 just seems to smile and dig deeper. Wanna go faster? The M8 Competition is always ready and able to answer the call. 

As with the M5 saloon, the M8 is all-wheel drive (the mighty traction the system confers means this heavyweight can match the McLaren 600LT 0-62mph) with the option – not recommended on public roads – to send the power solely to the rear wheels. Many might deem that option useless, but the M8’s entry fee does at least buy you the ability to radically transform the car’s character at the touch of a button. 

New 2020 Porsche 911 Turbo S vs BMW M8 Competition twin test review by CAR magazine

With every passing mile, familiarity and confidence grow. So too does a sense of relief that this all-wheel-drive system is keener, more rear-biased and more helpful than most. Even in the default mode the powertrain rapidly shuffles the power front to back, just as the nose starts to wash wide. So you try harder, get on the power earlier, and in response the  BMW just feels better and better – up to a point. The system is undeniably effective but you can’t help thinking it wouldn’t have to intervene so much if this near-two-tonne coupe (1885kg; nearly 250kg more than the 911) wasn’t carrying so much weight in the first place. Chicken and egg, you ponder; the all-wheel drive helps stick a Band-Aid over the weight, but junking the all-wheel drive would substantially reduce the weight.

Switch to Sport AWD (just one of the BMW’s myriad performance variables) and things become yet more rear-biased, meaning you can quell that hint of understeer with ample inputs of the throttle for a dose of power-assisted rotation. Doing so certainly ups the fun, and over the course of the day Sport AWD will prove a good middle ground – configured thus, the BMW calls to mind Mercedes-AMG’s similarly playful E63 S. Now the M8 Competition can be made to squirm a little, but when it shimmies it does so harmlessly – you won’t mess those posh seats.

But – and it’s a but that only gets bigger – is the BMW genuinely up for this kind of work? Yes, it wears an M badge. And yes it’s undeniably priced like a flagship. But with time you start to wonder if you might have the wrong tool for the job – or the wrong job for what is without doubt a hugely capable tool. Ultimately it isn’t the design, the number of seats, the position of the engine, the power output or the performance that marks the difference between a GT – a performance luxury car – and a true sports car. In the final analysis it is the driving position that separates one breed from the other.

BMW M8 Competition interior

In a true sports car you’re hugged by your seat, and cradled as close to the road as possible. (If there were a hole in the floorpan, you should be able to bend forward and run a hand over the tarmac speeding beneath you.) And not just for the beneficial physics: sitting low earths the nerve endings of car and driver alike.

DNA defines a car’s architecture and its accommodation. It’s the difference between the comfy-all-day Bentley Continental GT and the ultimately more involving Aston Martin DB11. Forget cylinder counts and race-car relations, the height at which the driver’s hip comes to rest within the machine is the number one decider when it comes to the intensity of the driving experience. And regardless of how effectively the M8 Competition is covering great swathes of southern Germany, there’s a nagging sense that M division’s ultimate driving machine might be more GT than sports car. 

Pulling over for a breather, hot brakes frantically – and stinkily – radiating their excess into the chill morning air, a quick look at the BMW’s DNA test does little to shake the sense that the M8 might be a sports car imposter. The first 911 Turbo – a widebody angst generator delivered with the devil inside – arrived in ’74 with ABS and a limited-slip diff but without anything else to help keep you pointing forwards. The steering was so unassisted it made your arms hurt, and the clutch pedal felt untenable until you tried the brakes, which were heavier still. And of course this was the car that introduced a viper-ish mixture of lift-off oversteer, power oversteer and turn-in oversteer to the Encyclopedia of Unfortunate Automotive Incidents.

Before the whaletailed widowmaker, the European touring car championship was dominated by various 3.0- and 3.2-litre lightweight coupes from Munich. But when the Batmobile went out of production, BMW lost the plot. While the hardcore M division rebelled and pushed through the charismatic if loss-making M1, BMW HQ went softly-softly. There were rare comets of greatness, such as the M635 CSi and the manual-transmission M850 CSi, but the truth is that BMW never managed to rediscover its former sports-car glory.

More recently, the 8-series borrows heavily from the 5-series and calls the old 6-series dad. It’s this confused, shared parentage that works against the M8. Departing R&D chief Klaus Fröhlich claimed that, even though the old M6 had fallen way short of its target, with the 8-series M GmbH had finally built a proper 911 fighter. The seasoned engineer should have known better, or proposed a more compelling i8 replacement instead. Or jumped on the supercar chaise longue for that tete-à-tete with McLaren that was later called off.

Instead, the Bavarian Motor Works opted to conceive a conventional high-performance 8-series coupe (plus cabrio and four-door derivatives) which, though capable of taking off like a slingshot in a straight line, is ultimately too heavy and imbalanced to really deliver when you’re past the detail and into the bald physics of the way a car interacts with a challenging stretch of road.

Weirdly, dropping into the Porsche feels like switching to the bigger car – the M8 is oddly cramped for a machine with such a generous footprint (criminally, the rear seats are no more practical than the 911’s), and the Turbo’s spacious and markedly less fussy interior feels like a sun-drenched beach after the BMW’s shady cove.

Porsche 911 Turbo S interior

Get moving and the 911’s initially underwhelming – blame a lack of rigour on your part when it comes to setting the thing up. Leave the drive mode controller unmolested and it’s possible to take this 641bhp 911 for a walkies with claws drawn in, fangs covered and eyes half-closed in a snooze. This limp cocktail of low revs and tall ratios, automatically shifted, will quickly rock your brain into a state of semi-sedation. Such an approach works wonders for your CO2 emissions and driving licence, but it’s fit only for rush-hour traffic. The excitement factor barely beats taking the bus. 

This drowsiness is cured in a heartbeat, with a switch to Sport or Sport Plus and a move to manual shifting, but it says much of the new 911 Turbo S’s altogether more serious character that it can be detected even here, in your first few miles in the car, while you’re still setting your driving position and trying to work out how lucky you’re feeling. 

The first hints are there at crawling pace, your palms sensing more driveline tension than was discernible in the previous car, and a texture and heft across the front axle that increases markedly with lock. For the more overtly mechanical drivetrain feel, thank the more overtly performance-focused all-wheel drive – the Turbo S’s front diff can now accept up to 80 per cent of the engine’s torque, and the transmission’s brain is keener to shuffle the shunt around for the best possible results. 

The chassis too is noticeably more muscular, not just in the more direct steering rack but in firmer suspension kinematics that unapologetically favour roadholding over compliance, even in Normal mode. Well aware that your flying time is in single-digit minutes, you prod the Porsche nonetheless. And in the few miles between here and the next rendezvous point you find yourself confronted by a level of ability that leaves you questioning your own. Cat-like reflexes far sharper and more prompt than have ever previously been available in any 911-badged Turbo, and cornering grip that slips back and forth between the hyper-physical and the simply unreal. And when it all gets a bit much (which it can, quite quickly…), the larger-than-life brake discs and the 10-piston calipers slow the runaway Porsche like a fighter jet hooking an aircraft carrier’s cable. What the hell happened to the 911 Turbo? 

Porsche 911 Turbo S

The more pertinent question is ‘who’ not ‘what’. And the answer’s Frank Walliser, the new sports car godfather at Porsche. With August Achleitner’s retirement, there was no one better qualified for the job than the wiry engineer who fathered the 918 Spyder and the Le Mans-winning 919 hybrids. Together with Andreas Preuninger from the GT department, Walliser took the decision to make future 911s even more focused and driver-orientated. This strategy extends even to the Turbo, which had over time evolved into an effortless high-speed autobahn mile-eater for rich, silver-templed CEOs used to staging lengthy conference calls at 125mph-plus. Thanks to all-wheel drive, a catalogue of comfort and convenience systems, trick aerodynamics and a brawny drivetrain capable of instant acceleration from virtually any speed, the Turbo had evolved to straddle the sports car and gran turismo orbits. Walliser and his team have put an end to this, and in some style. 

I jump back into the BMW, just to check we’ve a fight on our hands. On a handy straight it can’t quite stick with the Porsche, the Turbo S edging the M8 on power and torque while also saddling both with less weight to accelerate. Leaping 0-62mph the Porsche is half a second faster. But the BMW’s interface is superior, the red steering-wheel toggles marked M1 and M2 giving you immediate access to your preferred modes. The infotainment also provides single-touch direct access to the engine, dampers, steering, brakes and xDrive maps. The Porsche offers only one Individual mode in addition to Normal, Wet, Sport and Sport Plus, and only the BMW lets you decide exactly where all that grunt should go.

The M8 also has the more supple ride, unwavering stability on even ground, ample traction everywhere and more spine-friendly shifts. But they’re still there, those GT caveats. In its Sport and Track settings the steering is too grabby for its own good. Push on and the roll becomes increasingly challenging and your seventh sense begins to worry about the unchecked levels of yaw and pitch. These wayward movements are not the stuff of absolute confidence, even if the M8’s excesses look scarier from the outside than they feel from the bridge.

Last drive of the day; last chance for the Turbo S to prove itself special. It doesn’t let the opportunity go to waste. In short, where the BMW is lacking in a few key areas – behind the wheel you start to want more steering fidelity, more body control, more poise, more of a sense of connection – the Turbo S has a faintly embarrassing glut of them all. It changes direction with a racer’s intent, the steering direct and accurate (steering and brakes feel exactly the same irrespective of the selected drive mode, so there are no nasty surprises lurking in the critical twilight zone between nine- and eleven-tenths). The nose is fiercely tied down, even through heart-stopping autobahn esses at three-figure speeds. And while the engine is monumentally potent (it’d have to be to make the BMW’s V8 feel thin, which it does), there’s a holistic feel to this Turbo. Yes, it’ll overtake anything with absolute security and no little disdain, from any speed and with no notice. But it also has the sheer grip, the almighty stopping power and the mid-corner feel and finesse to cash the cheques its outlandish twin-turbo flat-six is capable of writing. 

So dazzling is the Turbo S as a complete modern sports car that you wonder if this car could have worn GT badging; a GT2 RS with a roadgoing remit. It feels that special.

Two five-star cars: but only one winner in our Porsche 911 Turbo and BMW M8 twin test


1st place: Porsche 911 Turbo S  ★★★★★
It’s fast – that’s what happens when you hook a monstrous twin-turbo flat-six up to all-wheel drive and fat tyres. But the sports-car reflexes and interactivity – they’re new

2nd place: BMW M8 Competition  ★★★★
The M5 sweeps all before it, so what gives? Fast saloons are safe ground for BMW – it’ll take a sports car to beat the new Turbo. And the M8 Competition isn’t one

Pre-flight briefing Porsche 911 Turbo S

Porsche 911 Turbo S spoiler

Why is it here?
Because the 911’s the sports-car benchmark, and the Turbo S promises to be something of an ultimate – the fastest and most complete road-focused 911. And the new one’s not like your father’s 911 Turbo. That was a numbers king keener on searing standing starts and swanning about like an apex predator than being hurried. The 992-gen Turbo feels different: more agile, more involving.

Any clever stuff?
As you’d imagine given the Turbo’s propensity for speed, active aerodynamics play a big part in the engineering. The car can tweak flaps in the front spoiler to achieve the best possible drag/downforce/cooling profile in real time. The control unit and compressor for this pneumatic system sit in the 911’s front boot, while the huge rear wing maintains the car’s aero balance as the front vanes do their thing. You also get a ferocious flat-six, based on the 9A2 Evo engine in the 992-gen Carrera. To that sound base engine (one-piece heads, crisp and accurate piezo-type injectors, electronic wastegate management), the Turbo adds bigger variable-vane turbochargers, a high-flow air intake system and GT2 RS-inspired manifolds. Power reaches the road via all-wheel drive and an eight-speed twin-clutch ’box. 

Which version is this?
The range-topping S coupe. There’s also a cabriolet. Key options here are the sports exhaust (£2180) and lower PASM Sport suspension (£1052). Ceramic brakes are standard. 

Pre-flight briefing BMW M8 Competition


Why is it here?
Because it’s BMW’s job to keep Porsche honest – for less money. It’s been doing it for generations, but the 8-series stretches BMW’s brand equity to its very limit – can you charge the best part of £150k for a car wearing the same badge as all those front-wheel-drive 1-series, the badge of a company that pulled out of all top-level motorsport in the wake of the emissions scandal? Munich certainly thinks so, and senior BMW engineers were punchy at the car’s unveiling. ‘The two-door 6-series came quite close to challenging the Porsche 911,’ R&D chief Klaus Fröhlich told CAR. ‘The 8-series coupe closed that gap. The M8 has what it takes to secure the sports-car crown in the 600bhp segment.’

Any clever stuff?
The 8’s structure is closely related to that of the 5-series, albeit reinforced with composite elements to increase torsional rigidity. The engine’s a masterpiece. An uprated version of the already mighty unit in the M850i, the full M engine gets upgraded cooling and lubrication systems (including a second feed to keep the oil flowing through long, high-load corners on track) and a high-pressure fuel-injection system. It’s bolted to the car via more rigid mounts, sharpening the drive and communicating more of the V8’s efforts to the cockpit. Drivetrain is as per the M5 Competition – a rear-biased performance all-wheel-drive system that can be locked to rear-drive only. Non-M 8-series models have rear-wheel steer; the M8 doesn’t, to aid predictability. 

Which version is this?
The Coupe – you can also get an M8 Convertible and the four-door Gran Coupe. In terms of key options, this car has the carbon-ceramic brakes (a £7995 option) and the M Driver’s Package (£2095), which lifts the speed limiter and gets you a day’s BMW Intensive Driving Training course.

More comparison tests by CAR magazine

By Georg Kacher

European editor, secrets uncoverer, futurist, first man behind any wheel