They’re four-doors posing as two-doors but which is the better impersonator? We test the BMW M235i xDrive Gran Coupé Steptronic and the BMW M850i xDrive Gran Coupé Steptronic...

To many motoring enthusiasts, the act of attaching the coupé suffix to anything with more than two doors is seen as something of a cardinal sin. But with vehicular definitions expanding to meet buyers’ diverse aspirations, many lines have been blurred. For instance, outside of the mildly jacked-up and plastic-bottomed hatchbacks with “cross” in their names, there’s even some debate as to where crossovers end and SUVs begin … and that was before BMW further muddied the waters by labelling its X5 an SAV (sport activity vehicle). In this alphabet soup of categories, the concept of a four-door coupé reared its head and with understandable reason; buyers aspire to the sporty looks of a traditional coupé but need rear accommodations beyond a chair-shaped, upholstered parcel shelf and a useable boot.

Cue BMW’s crop of Gran Coupés; essentially four-door models with two-door aspirations of svelte styling and sportiness. Here we look at the polar ends of this particular automotive niche to see if the results of coupé imitation can flatter.

Styling

When talking about coupés –“gran” or otherwise – it’s all about the profile. Buyers in this bracket are willing to forego the spaciousness and practicality of a conventional three-box sedan to be able to revel in the arcing roofline and boat-tailed rear drama of a coupé. But while both cars here no doubt grab attention, it’s interesting to see just how each has gone about wrapping sheetmetal around a four-door coupé frame.

The M235i Gran Coupé is based heavily on the 1 Series – being spun off the same UKL2 compact modular platform – but this time BMW has attempted to visually distance the two beyond a mere three-box profile. The M235i GC’s nose features a more ventrally compressed take on the 1’s kidney grille and the headlamps boast scalloped bases along with more prominent C-shaped outer air dams which lend the front a broader, low-slung appearance.

Otherwise, from nose to B-pillar, it largely mirrors the 1. Beyond that things begin to get ... interesting. The thinner glasshouse and rear doors’ broader sheetmetal conspire with a considerable drop in the roofline to all but conceal the signature Hofmeister kink before levelling out onto a stubby boot deck and plunging into a tail that’s adorned with dramatic slashes of brakelamp á la 8 Series. Factor in our test unit’s Snapper Rocks Blue metallic paintwork and it’s certainly an eye-catcher.

Although we’d stop short of deeming the M235i GC visually disjointed, its design is a little difficult to digest, especially when parked alongside the M850i GC. Where the smaller car’s bluff, jacked-up rear seems caught in a bizarre transition between coupé and hatchback, the M850i GC’s profile appears to have been effortlessly smoothed over its frame, with a more measured descent of its roofline into a taut tail. Granted, the M235i had the somewhat squat and conservative hatchback as a more challenging starting point than the M850i’s shapelier coupé donor, but the larger car undoubtedly wears its proportions more assuredly; even the presence of usually overt M styling bits – such as the rear diffuser and sill extensions – aren’t jarring.

When it comes to a four-door exercise in emulating the visual grace of a coupé, the M850i GC is about as close as it gets.

Interiors

It’s here where the two Gran Coupés begin to diverge, with the M235i GC clearly targeting a younger, more extrovert audience. As with large portions of the exterior, the cabin shares much of its design with that of the 1 Series, and that’s not a bad thing: it’s simple, clean and feels suitably premium and well put together. With its anthracite roof liner and largely black and gunmetal trim, the cabin does feel rather dark, but the standard Illuminated Boston door and facia panels liven things up with blue slashes of light in a tartan-esque pattern.

The seats are targeted at younger (read: more lithe and less sedentary) frames, with supportive cushions and firm bolstering on the sportier side of the seating spectrum. That said, once you’ve managed to bed in to your favoured driving position – an easy task given the low starting point of the height adjustment and plenty of ways to set the steering column – the driver’s spot in the M235i GC quickly becomes a good fit.

Things aren’t as comfy for folks in the back, though. The rear passengers pay the price for that tapering roofline. The perennial “six-footer behind six-footer” exercise was decidedly cramped, with little in the way of kneeroom and crowns grazing the headlining.

Thankfully it’s not all doom and gloom at the M235i GC’s tail. Open that short rear deck lid and you’re greeted with a boot that cuts deeper into the car than you’d expect, serving up a useful 272 litres of space and expanding to 768 litres with the 40:20:40-split rear seatbacks stowed flat.

By contrast, the M850i GC’s cabin feels far lighter and less claustrophobic. By four-door coupé standards, the 753 mm of rear legroom is sprawl-worthy and the 803 mm of headroom back there means rear accommodations are practical and comfortably proportioned. Like the M235i GC, a larger than expected boot dwells beneath that tapered tail. The M850i GC’s likely audience will find the 312/888 litres golf bag-friendly.

But it’s the perceived quality and detailing that makes getting behind the wheel such a visual and tactile treat. Finding a low-slung but eminently comfortable attitude in those well-sculpted seats is a breeze and, unlike the M235i GC, the interior isn’t lifted from a platform-sharing stable-mate (5 Series). Instead, the M850i GC’s facia array – with its compact instrument binnacle and broad sweep of centre console– is visually appealing and a sporty nod to that of the original 8 Series.

You’ll battle to find a surface that isn’t lavishly satin-chromed, veneered or padded with stitched leather. It feels well-crafted and befits the car’s considerable asking price.

On the road

Given its close mechanical relationship to the tepidly received M135i, there was concern the Gran Coupé would fall foul of the accomplished but not particularly entertaining road manners of the hatchback. In terms of those overall road manners, the M235i GC offers more of the same in a slightly longer and marginally heavier package. Those 19-inch rims wrapped with 35-profile rubber, along with the 10 mm lowered and stiffened M Sport suspension setup, equate to excellent grip but at the expense of ride comfort, which becomes crashy over even slightly uneven road surfaces.

Thankfully, the steering feels direct and well weighted, and goes hand in hand with a taut chassis that does a decent job of reining in body roll.

Now that the world has come to terms with the fact that BMW’s “35i” suffix no longer denotes a six-cylinder powerplant, it’s possible to appreciate what a flexible and well-rounded engine the new turbocharged four-cylinder is.

With 225 kW and a brawny 450 N.m of torque across a broad swathe of the rev range, the M235i GC’s engine feels responsive and punchy. While the numbers on paper and the swing of the rev needle suggest impressive performance – our 5,41-second 0-100 km/h acceleration labels it brisk – the M235i GC doesn’t feel especially exciting to drive.

It’s likely BMW’s ARB – a slip controller in the car’s ECU that regulates the stability control system’s intervention when traction is compromised – and Performance Control (which brakes the inside wheels around a corner to counter power understeer) provide just enough of a barrier between the engine’s brawn and the tyres putting it to the road to make progress fast and fluid, but not necessarily fun. This restrained approach would be understandable in a car that could double as a comfy long-distance tourer but the M235i GC doesn’t have that string to its bow.

It’s a criticism that can’t be laid at the M850i GC’s feet. Although M Sport-fettled and similarly thinly shod on its 20-inch wheels, the ride is supple and well damped; only occasionally becoming fidgety at low speeds.

We’ve long been fans of BMW’s turbocharged 4,4-litre V8 and its application in the M850i GC is one of the finest. Opt for one of the more comfort-oriented drivetrain presets and it stirs quietly in the background, gently wafting that 2,1-tonne frame while the transmission slips almost unnoticed through the gears. Select a sportier preset, bury the throttle and the M850i GC awakes, the gearshifts and long-travel throttle become more hair-triggered in their responses and the soundtrack a muffled snarl; any hint of easing off the pedal is met with resonant crackles from the adjustable sports exhaust. However, it’s the surge of low-end torque that grabs your attention. Arriving with disarming immediacy, together with the AWD system’s tremendous traction, that shoulder-pinning 750 N.m of torque makes its presence felt between 1 800 r/min and 4 600 r/min.

Although, the M850i GC isn’t purely a straight-line rocket. Its ability to crack the 0-100 km/h sprint in just 4,15 seconds is no mean feat, yet, it’s the way in which the car harnesses that power, making it easier to wield the performance on offer. A car of the M850i GC’s proportions would normally be met with wallow and clumsy lateral weight transfer under hard cornering during swift directional changes. Here, the adaptive dampers and four-wheel steering work wonders in blotting anything unpleasant, rendering the big BMW deceptively agile.

The only component stopping it from being labelled sporty is the steering. In something this size, a rack with quick gearing would likely be the drop of ink in the M850i GC’s clean waters, undoing all that impressive work elsewhere. The steering is light and not as communicative as the one in the similarly positioned, sportier Porsche Panamera. It does, however, suit the car’s cruising credentials. With the comfort, power and refinement on offer, it has the makings of an excellent continent crosser.



TEST SUMMARY

As we saw in our test of the Mercedes-AMG GT53, the melding of coupé and sedan is often an exercise in compromise; it’s the same with these polar ends of BMW’s Gran Coupé offerings. But it’s the weight of intended purpose of combining practicality and performance that illustrates how best to strike a balance.

In relation to both the M235i and M850i GC, we could argue there are more conventional four-door models in the stable that cover those bases – albeit without their visual panache – but of the two, it’s the larger car that best accomplishes this.

Eye-catching as it is, the M235i GC’s execution is muddled, almost caught between a hatch and hard-to-place four-door. It’s fast and accomplished, if not overly entertaining to drive, but its cramped cabin and crashy ride mean it’s not engaging enough to be sporty nor comfortable enough to be a tourer.

The M850i GC better balances these traits; perhaps erring on the soft side of dynamic handling and that’s not a bad thing. With its surprisingly spacious rear quarters and generous boot, it’s a rare example of a four-door coupé we could recommend alongside its purebred two-door sibling. If imitation is the greatest form of flattery, the M850i Coupé should feel rightly honoured, perhaps a little unnerved, by its four-door impersonator.  

M235i Gran Coupé: 3½ stars
M850i Gran Coupé: 4 stars