BMW M8 vs Porsche 718

What's the difference?

With dramatic looks, a luxurious spec, and impeccable quality, the BMW M8 Competition Gran Coupe remains supremely well controlled as it delivers eye-widening performance and amazing dynamics. But there’s an ‘edge’ to the experience you need to be ready for. If I was determined to head for the Aussie ‘fast lane’ in a BMW 8 Series Gran Coupe I’d opt for the M850i and pocket a lazy $71K (enough for a cheeky M235i Gran Coupe to add to your collection).

If this is to be the end of the 718 as we know it, then it is an end to be remembered. Porsche has produced something special in the Spyder RS, a sports car that can compete with the 911 on any stretch of road - which is something so few cars can claim. The focus on performance has driven the entire concept of the car, but all the elements work in harmony, with form and function coming together.

Want to start a vigorous car enthusiast discussion (more a verbal punch-up)? Simply ask whether a four-door car can be a coupe.

Traditionally, the answer is no, but over time numerous automotive brands have applied that description to cars with more than two doors, including SUVs!

So, here we are. A four-door ‘Gran Coupe’, and the M8 Competition version retains the smoothly tapering turret and frameless side glass that help give selected BMW four-door models the same swoopy, coupe look.

At close to 4.9m long, a fraction over 1.9m wide, and under 1.4m high, the BMW 8 Series Gran Coupe has a firmly planted, low-slung, wide-track stance. Always a subjective call, but I for one, think it looks stunning, especially in our test car’s ‘Frozen Brilliant White’ matt paint finish.

In an era of comically oversized BMW grilles, things are relatively under control here, with a bright black finish applied to that ‘kidney grille’, as well as the huge front bumper air intakes, front splitter, front fender vents, exterior mirrors, window surrounds, 20-inch rims, lip spoiler on the boot, rear valance panel (incorporating a functional diffuser), and quad exhaust tips. The roof’s black, too, but that’s because it’s made of carbon-fibre.

Overall the M8 Competition Gran Coupe is a compelling combination of strong, confident character lines along the bonnet and lower flanks, with tightly wrapped curves following the high hip line, and more organically irregular, yet distinctly BMW shapes in the head- and tail-lights. 

The interior is a beautifully balanced design with a broad centre console sweeping up to the middle of the dash and wrapping around to focus on the driver, in typical BMW fashion.

 The multi-adjustable sports front seats are immaculate, with high-end quilting in the centre section matching a similar treatment in the doors. The dark grey (full) leather trim is offset by carbon and brushed metal trim elements for a cool, calm and focused feel.

Crack the bonnet open and a spectacular ‘BMW M Power’ carbon cover dressing the top of the engine is guaranteed to impress friends and family.

As the pinnacle of not only the current 718 range, but potentially the entire combustion engine era of the Boxster, Porsche has pulled out all the stops for the Spyder RS.

This includes major changes to the design, but none are purely for aesthetic reasons and instead are driven by the search for performance; and the fact they make the 718 look tougher, meaner and more purposeful than ever before is just a bonus.

It’s a comprehensive redesign that starts at the bumper with a new front lip spoiler to enhance downforce. Then there’s a pair of NACA ducts on the lightweight bonnet to improve brake cooling without compromising aerodynamic drag. The lightweight front fenders include wheel arch vents to stop any potential for front-end lift at high speeds.

And the fenders aren’t the only component that’s gone on a diet, there’s a lighter exhaust, lighter wheels, lighter bonnet, lighter roof, lighter door panels and even lighter carpets on the inside. All up, the Spyder RS tips the scales at 1400kg, which is 40kg lighter than a standard 718 Boxster.

If it’s still not light enough, you can opt for the optional 'Weissach Package' (which was fitted to our test car), which brings even lighter 20-inch forged magnesium wheels and carbon-fibre reinforced plastic for a range of parts including the front luggage compartment, rollover bars and ducktail spoiler on the Gurney flap – plus some cosmetic enhancements.

And we still haven’t even touched on the biggest design change yet - the rear half of the car. Starting with the roof, which Porsche actually calls a ‘sunshield’ and ‘weather guard’ because it’s a stripped down version of what the brand usually uses, to save weight and let the glorious engine noise into the cabin uninterrupted.

But it’s also necessary because the entire rear engine cover has been redesigned to accommodate the larger engine that Porsche has installed in the Spyder RS, a 4.0-litre six-cylinder instead of the usual turbocharged four-cylinder ‘boxer’ engines.

While the Spyder RS looks great with the roof/sunshield on or off, frankly the removal process is much too complicated and requires repeated viewings of a YouTube tutorial to still get it wrong.

While owners will (likely) eventually get the hang of it, it will always be a clunky and awkward process and that’s just the price of being so focused on performance, which you can accept or not.

Inside that ethos of performance over practicality continues, with sports seats, an Alcantara-wrapped steering wheel and even the previously mentioned lightweight carpet floor mats.

It’s a purposeful, rather than luxurious, cabin, but that perfectly suits the nature of the Spyder RS. Our test drive included several long stretches behind the wheel and at no stage did it feel uncomfortable or impractical, despite its stripped-down design.

Of the M8 Competition Gran Coupe’s 4867mm overall length, 2827 of it sits between the front and rear axles, which is a pretty healthy wheelbase for a car this size (and 200mm more than the 8 Series two-door coupe).

Space up front is generous, and one upside of a four-door, rather than two-door coupe, is you’re not struggling quite so much for space to get in and out when parked next to other cars.

Once inside, there’s plenty of storage up front, with a large lidded box/armrest between the front seats, twin cupholders in the centre console, as well as another covered area for wireless phone charging and extra bits and pieces in front of that. Long door pockets provide space for bottles, and the glove box is a decent size. There’s 12V power as well as USB sockets for media connection, with charging outlets in support.

At first glance you’d swear the rear seat was designed as a two-seater only, but when push (literally) comes to shove a centre passenger can squeeze in, legs straddling the rear console.

In terms of legroom, at 183cm (6’0”) I could sit behind the driver’s seat set for my position with knee room to spare, but headroom is another matter, with my noggin making solid contact with the soft Alcantara headlining. It’s the price you pay for this car’s racy profile.

There’s a neatly trimmed storage box and two cupholders in the fold-down centre armrest, plus door pockets with enough room for small bottles. The rear console houses dual climate controls, twin USB power sockets, and a small oddments tray, as well as buttons for the optional rear seat heating fitted to our test car ($900).

The 440-litre boot is a bit like the car itself - long and wide, but not very high. The rear seat split-folds 40/20/40 if you need more space, and the boot lid is automatic with a hands free function. But don’t bother looking for a spare of any description, a tyre repair kit is your only option.

One area where the 718 range is starting to show its age quite dramatically is the in-car technology. While Porsche’s native system is relatively user-friendly, the lack of wireless Apple CarPlay or Android Auto in any capacity is deeply out-dated; and was frustrating for this Android using reviewer.

Given the age of the current 718 platform, and the impending arrival of the new model, it’s understandable that the multimedia system didn’t get an overhaul, but for a $350K car it does feel a bit behind the times.

In practical terms the Spyder RS is a bit of a struggle if you plan to go away with it. We managed to get a small suitcase and backpack in the under bonnet storage, but that was at capacity. While the addition of the larger engine removes any meaningful rear storage space.

The bad news is, the Spyder RS costs just over $200,000 more than the entry-level 718 Boxster, which is not a small sum of money. The good news is, for that $200K, Porsche has overhauled the 718 from nose-to-tail and enhanced it in nearly every aspect.

There’s a raft of mechanical changes that we’ll get to later on, to help justify the $334,200, plus on-road costs, asking price, but from a specification perspective there are some notable inclusions. 

For starters it comes with the 'Porsche Communication Management' (PCM) multimedia system, which includes in-built navigation and Bluetooth connectivity, as well as a 110-watt sound system.

But Australian delivered cars get an even higher level of standard equipment than other countries, with LED headlights including 'Porsche Dynamic Light System' (PDLS), cruise control, digital radio, rear 'ParkAssist' with reversing camera, 'Light Design Package', tyre fit set and windscreen with grey top tint, plus a no-cost optional Bose Surround Sound System all included.

It may be $200K more than 718 but compared to a 911, it actually makes a pretty compelling value argument. A 911 Cabriolet Carrera S starts at $342,700 (plus on-road costs), making that Spyder RS $8500 cheaper and a genuine alternative to its ‘big brother’.

Then, when you compare it against similar mid-engine European sports cars, such as the Maserati MC20 (from $510,000) or McLaren Artura (from $477,310) the Porsche looks like a bargain; relatively speaking, of course.

The M8 Competition is powered by an all-alloy, 4.4-litre twin-turbo V8 engine, featuring direct-injection, as well as the latest version of BMW’s ‘Valvetronic’ variable valve timing and ‘Double-VANOS’ variable camshaft control, to produce 460kW (625hp) at 6000rpm, and 750Nm from 1800-5800rpm.

Designated ‘S63’, the engine’s two twin-scroll turbos are located, along with a cross-bank exhaust manifold, in the engine’s (90-degree) ‘hot vee.’ 

The idea is consistent transmission of exhaust energy to the turbos for improved response, with the reversal of usual practice completed by inlet manifolds positioned on the engine’s outer edges.

Drive goes to all four wheels via an eight-speed ‘M Steptronic’ (torque converter) auto transmission with ‘Drivelogic’, and dedicated oil cooling, as well as BMW’s ‘xDrive’ all-wheel drive system.

The xDrive set-up is built around a central transfer case housing an electronically-controlled, variable multi-plate clutch, with front to rear drive distribution set to a default 40:60 split.

The system monitors multiple inputs including, wheel speed (and slip), acceleration and steering angle, and is able to vary the ratio up to 100 per cent rear thanks to the ‘Active M Differential.’ 

The key stat for the engine is the cylinder count. Gone are the four cylinders and instead it’s a return to Porsche’s iconic flat-six.

Specifically, the same 4.0-litre six that Porsche uses in its 911 GT3, which is a lot of engine to squeeze into the middle of this lightened sports convertible.

In order to keep the 718 in its place (beneath the 911), Porsche has slightly detuned the engine, so it makes 368kW/450Nm (compared to 375kW/460Nm in the 911 GT3), but the German brand has never worried about a kilowatt contest and instead prefers to focus on driveability and the other elements that make a drive great.

To that end the combination of air-intakes next to the headrests and the lightweight stainless steel exhaust (which gets titanium tips on the Weissach Package) helps the Spyder RS sound like a Carrera Cup racing car when you really wind it up to its 9000rpm redline.

Not that the performance isn’t spectacular, though, with Porsche claiming it takes the Spyder RS just 3.4 seconds to run 0-100km/h, only 10.9 seconds to get from 0-200km/h and will hit a top speed of 308km/h.

The engine is paired to a seven-speed dual-clutch auto transmission (or PDK in Porsche-speak) that the company claims has “short-ratios”, but with peak power not hitting until 8400rpm and peak torque from 6750rpm, you don’t have to rush the ratio changes.

Claimed fuel economy for the combined (ADR 81/02 - urban, extra-urban) cycle is 10.4L/100km, the M8 Competition emitting 239g/km of CO2 in the process.

Despite the standard auto stop/start function, over a week-long combination of city, suburban, and freeway running we recorded a (dash-indicated) average of 15.6L/100km.

Pretty thirsty, but not outrageous when you consider this car’s performance potential, and the fact that (purely for research purposes) we exploited it regularly.

Recommended fuel is 98 RON premium unleaded, and you’ll need 68 litres of it to fill the tank. That equates to a range of 654km in line with the factory claim, and 436km using our real-world number as a guide.

Porsche says the 4.0-litre engine in the Spyder RS uses 13.0L/100km, which is a big number for what is a relatively small car. But that engine is highly-tuned and built for performance not efficiency, so it’s something owners will need to accept.

Our test drive included some long highway stretches, as well as some spirited driving and urban commuting, so a good mix across all conditions, and we saw consistent returns around the 15-16L/100km range.

It has a 64-litre tank, which means a theoretical driving range of around 490km, assuming you can hit the official claim.

There’s something teutonically symmetrical about the way the M8 Competition Gran Coupe delivers its prodigious thrust.

Peak torque of no less than 750Nm is available from just 1800rpm, remaining on full song across a broad plateau all the way to 5800rpm. Just 200revs later (6000rpm) peak power of 460kW (625hp!) takes over to finish the job, with the rev ceiling sitting just over 7000rpm.

That’s enough to slingshot this 1885kg bruiser from 0-100km/h in 3.2 seconds, which is supercar fast. And the engine and exhaust noise produced by the 4.4-litre twin-turbo V8 during such rapid acceleration is suitably brutal, courtesy of electronically-controlled flaps in the system opening up. 

On a more civilised drive you can reduce the exhaust noise via an ‘M Sound Control’ button on the centre console.

The eight-speed auto is fast and positive, especially in manual mode, which dials up the fun via wheel-mounted paddles. And when it’s time to direct this car’s forward momentum into lateral movement BMW has brought in the engineering heavy artillery.

Despite its frameless door body structure the M8 Competition Gran Coupe feels solid as a rock thanks in no small part to its ‘Carbon Core’ construction, using four primary components - carbon-fibre-reinforced plastic (CFRP), aluminum, high-strength steel, and magnesium.

Then the ‘Adaptive M Suspension Professional’ (with active anti-roll stabilisation), the tricky xDrive continuously variable AWD system, and active M Sport diff combine to keep everything under control.

Suspension is a double wishbone front, five-link rear arrangement, with all key components in alloy to minimise unsprung weight. In concert with the electronic wizardry on-board, it helps keep the M8 buttoned down with only modest body roll in enthusiastic cornering, as the rear-biased AWD system seamlessly distributes drive to the axle and wheels that can make best use of it.

The price you’ll pay for the track-ready tune is in compromised ride comfort. Even in the ‘Comfort’ setting, the M8 Competition is firm, and feels corrugations and imperfections to a surprising degree.

An alignment of the BMW 8 Series planets left me with the keys to this car and the M850i Gran Coupe (also using the Carbon Core body) at the same time, and the difference between their softest settings is appreciable.

Also be aware that at 12.2m the M8 Gran Coupe’s turning circle is substantial, and it’s just as well all that camera, sensor and self-parking tech is available to help you guide this ship into port.

The M8’s electrically-assisted, variable-ratio steering features an ‘M’ specific calibration to deliver satisfying precision and good road feel. But in similar fashion to the ride a noticeable amount of unwelcome feedback comes through to the wheel.

The fat Pirelli P Zero rubber (275/35 fr / 285/35 rr) grips hard, and the monster brakes (ventilated all around, with 395mm rotors and six-piston calipers up front) wash off speed without fuss or fade.

But overall, you’ll have to live with a less refined drive when you sign on for the M8 Competition. Straight away it feels faster but lacks the M850i’s lighter touch. No matter which drive or suspension mode you select, responses are more aggressive and physical.

To fully explore and enjoy the M8 Competition’s abilities it feels like the race circuit is its most appropriate habitat. On the open road, the M850i is all the Gran Coupe you’re going to need.

I’m only giving it a nine out of 10 because perfection is hard for any car to achieve, but the 718 Spyder RS goes as close as any car I’ve driven. This is a masterpiece of modern sports car design, pushing the 718 closer to the 911 than ever before, which is something Porsche has clearly tried to avoid so as to not tarnish the image of its flagship.

But with the 911’s 4.0-litre flat-six in the middle of the 718, plus its more compact dimensions, the lightweight nature of the Spyder RS and the raft of chassis and handling enhancements, this really does leave you questioning ‘do I really need a 911?’

The steering is fantastically direct, the chassis responds to every input with precision and feedback and the braking is strong and consistent. Which helps because that engine is so good it launches you with ferocity and a glorious noise (as good as anything on the market today) whenever you squeeze down on the accelerator.

The highest praise I can give the Spyder RS is not that it was a dream to drive on winding, challenging roads, but that it was just as enjoyable on a trip to the shops or cruising down the freeway. Any drive in this car is a genuine pleasure.

This is another area where the 718 is showing its vintage, with very little in the way of active safety features. There’s the required stability control, as well as airbags for driver and passenger, plus the previously mentioned reversing camera. But that’s it, there’s no autonomous emergency braking, no lane-keeping assist or even adaptive cruise control.

While that may sound shocking to some, there’s never a moment where you feel unsafe in the 718. It feels incredibly stable and responsive on the road, as the onus falls back upon the driver to pay attention and make smart choices.

There’s no ANCAP rating for the 718, or any Porsche, so it is a question of putting your faith into Porsche’s in-house safety measures.

BMW offers a three year/unlimited km warranty, which is at least a couple of years off the mainstream market pace, and lagging other premium players like Mercedes-Benz and Genesis, both sitting at five years/unlimited km.

Roadside assistance is included for the duration of the warranty period, and the standard ‘Concierge Service’ provides everything from flight information, to global weather updates, and restaurant recommendations, from a real human.

Technically, service is ‘condition based’ with the car telling you when it’s time to hit the workshop, but you can use every 12 months/15,000km as a guide.

BMW Australia offers ‘Service Inclusive’ packages that require customers to pre-pay for servicing, allowing the cost to be covered off in finance or leasing packages and reducing the need for concern about paying for maintenance further down the track.

BMW says there are different packages available, from three to 10 years, or between 40,000 and 200,000km.

It’s difficult to give the Spyder RS a clear score here because Porsche is cagey on the details. The public dealer websites indicate annual oil maintenance is required, with additional servicing every two years or 15,000km. 

How much that will cost is unclear, as despite the rest of the 718 range having publicly available prices, there were no such details for the Spyder RS (or even its Cayman sibling, the GT4 RS).

For reference, the 'standard' 718 requires oil maintenance ($895) for the first annual service and an inspection ($1500) the year after. Those costs continue to alternate annually out to eight years/120,000km.