When the Mercedes-AMG C63 S last battled BMW’s M4 Competition Package, it came away bruised. Can the latest version redress the balance?

This feels like the automotive equivalent of a Bavarian bar brawl. A backstreet, beer-fuelled bust-up between two strongmen from neighbouring German cities. In the black corner is the alarmingly threatening and recently revised Mercedes-AMG C63 S Coupe, whose belligerent elbows-out stance born from bespoke wide arches means you’ll not want to spill its stein of lager on a night out. And in the opposing and, er, equally black corner is the latest BMW M4 with Competition Package, which while trading a fair bit of muscle bulk to the AMG, fights back with its renowned athleticism as a tyre-smoking street fighter.

When they met in an evo Supertest back in 2017, accompanied by the then-new Audi RS5, it was the AMG that promised the most, and threatened to overshadow the other pair with its eye-watering stats and initial bravura, only for the M4 to shine brightly on the road, on the circuit and on the strip. Whichever way you looked at it, whether lap time or B-road rewards, the M-car hammered home its advantage, repeatedly, until it came away an easy winner. In doing so, it became one of the quiet heroes of 2017; a car we were all a bit surprised to find we had a significant emotional attachment to in the autumn of its lifetime. Now it’s time to see if AMG’s mid-life tweaking can redress the balance of power.

It doesn’t take long for the C63 S to weave its spell. Given the $165,900 price tag, you’d hope that to be the case, but there’s a real magnetism here that transcends the rather more humble C-class roots and gives it an air of confidence even at that lofty price point. It’s a car you can’t help but look back at once parked; an automotive superhero, its tunic in danger of tearing apart under the strain of that rampant 375kW and 700Nm (both unchanged from before), so very larger-than-life and all the better for it. In an age when we’re all nervously looking over our shoulders at fully electric performance cars with dizzying outputs and performance numbers but precious little in the way of identifiable soul, the C63 S is a beautiful anachronism, offering a thrill that feels illicit and indulgent.

The new nine-speed ’box (the old one had a mere seven gears) uses the same wet clutch in place of a torque-converter, and frankly doesn’t appear to make a great deal of difference to the overall driving experience. I’m sure it aids economy – let’s face it, not this car’s strong point – but if you want manual control, as I very quickly yearn for, there are even more gears to choose from, which isn’t always helpful. You soon learn to forget about the top two or three in normal driving, for they are more like overdrive ratios to save fuel during a cruise. Let the V8 pull hard from low revs in a high gear, rejoicing in the relentless surge and demonic throb from the four tailpipes, and you can’t help but ponder if just four ratios would do the job, such is the spread of torque.

As for the 4.0-litre engine, it’s a continuing thing of fascination; I mean, just how does AMG fit a pair of turbochargers to a V8 and manage to retain almost all of the aural appeal and throttle response of its revered old naturally aspirated units? Apart from Ferrari’s freakily responsive V8 in the 488 Pista, no other manufacturer’s engine can match this cocktail of ability and personality.

In its most relaxed setting the C63 S is effortless everyday transport, a quiet rumble from beyond the front bulkhead summoning instant overtaking muscle, and the ride quality reasonably relaxed. And what settings there are too. You see, that’s one of the other changes with this revised car: there are now six ‘AMG Dynamic Select’ drive modes (Slippery, Comfort, Sport, Sport+, Race and Individual), but there are also four ‘AMG Dynamics’ modes (Basic, Advanced, Pro and Master) that tailor the ESC and torque vectoring. And, of course, the variable damping, engine response, gearbox and sports exhaust can all be configured individually too. There’s undoubtedly a way of adding up all the differing permutations, but I don’t want to even go there.

Thankfully, part of this new package is a mode switch and some configurable buttons on the new AMG steering wheel, so you have more accessibility options beyond just diving into the main screens, plus you can assign favourite set-ups to the Individual mode. Talking of screens, the C63 S has the new fully digital cockpit, as seen on other new AMGs recently, with a raft of layout options and some very sharp graphics. Frankly, it’s so multi-layered that you just need to park up, switch the engine off, and study the possibilities for 20 minutes if you’re to properly understand how it all works. Is that a good thing? It depends whether you think the C63’s extraordinary adaptability to roads and conditions and different driver abilities makes it a more capable machine, or that it is all unnecessary complication away from its core competencies.

It’s not just the crackling motor that makes a positive initial impression: the chassis is also immediately alert, and relishes you driving in an enthusiastic manner. There’s very little slack in the way it moves away from the straight ahead, and it imparts a real sense of connection between driver and what’s happening down at the road’s surface. You’re always aware that some prudence is required with the throttle, for it’s patently obvious that the C63 S will oversteer for Baden-Württemberg on demand, but it feels tight, focused, determined. It also feels impregnable – as though it will smash any road or rival into submission through power and iron-fisted control alone.

None of which bodes well for the M division machine. However thick-set and bulged-of-bonnet it may appear in the metal, it’s hard not to imagine it being overawed by the Merc, a theory backed up by the brutal numbers of its Stuttgart rival: the M-car lags behind by 44kW and 150Nm. Then there’s the noise. The BMW straight-six has a snarly, boisterously loud note, particularly from a cold start, but it’s easily drowned out by the AMG’s rolling thunder, and it predictably lacks the different phases and evolving soundtrack that you’d find in an old E46 M3.

Even in the first few metres, often where a really good car provides some pretty damned clear signposts that it is going to enrich your motoring life, the M4 fails to land any notably clean punches. This car ‘enjoys’ a new design of M steering wheel, but it still feels huge, both in overall circumference and rim diameter, removing much of the initial subtlety to the way the car steers, the rest seen off by a rack that seems oddly disjointed in the way it responds.

This particular M4 has the seven-speed twin-clutch transmission, as most sadly do. The DCT removes the interaction and novelty a three-pedal variant would possess, and there’s also the initial mode fiddling to get one’s head around, which while nothing like as extensive as in the AMG, still takes a little getting used to. I also feel obliged to point out that the BMW’s dash and infotainment set-up is clearly very dated next to the Merc’s spangly new offering – but I find the M4’s dials perfectly legible, and the day we start judging driver’s cars by TFT screens will be a sad one indeed. But if that sort of thing is important to you then it’s worth noting.

Yet there’s a truism about this pair that hasn’t changed – a couple of extra gears and a fancy instrument panel or two doesn’t alter the fact that they exist in the same bisecting orbits as they did 18 months ago. The AMG holds almost all the aces on initial exposure, but the more you drive them, the more the M4 shines, while the AMG, hardly paling under the same treatment, doesn’t really add much more to its initial offering. It’s still a subject of wonder and curiosity that the 2018MY-onwards Competition Package is essentially the same car as the original 2014 M4, given the depth of its positive qualities compared to the wayward and spiteful personality once possessed. The Comp Pack changes – including stiffer springs, dampers and anti-roll bars, 20-inch wheels and a sports exhaust – bring a more focused remit, and along with further undocumented tweaks during 2017-18 transformed the M4.

Sharpen up the engine setting, but don’t go too firm on the adaptive dampers, increase your speed, and the black Beemer suddenly wakes up with the metaphorical jolt of a Labrador that’s just realised lunchtime is already under way and it might miss out. Listen again to what that big steering wheel is telling you, and to the subtle message filtering through from the squab of the unusually styled bucket seats. Notice how every little millimetre of steering input is making a difference now you’re on lock, how the balance of the car shifts around with the application of throttle and the way you enter a corner. The M4 breathes more with the road than the AMG. It really flows even though its ride is relatively stiff in normal driving, and it doesn’t feel like it needs to manage its bulk in the same way, because it doesn’t have to. There’s always a feeling that the AMG needs to keep everything under ruthless control, lest the masses (AMG claims 1745kg, but our similarly-specced Supertest car tipped the scales at 1847kg, compared to the 1645kg when we weighed the M4 CP – BMW claims 1570kg) get out of hand and wayward body control extends into something more serious.

The M4 seems unburdened in this way, and driving therefore becomes much more of a three-dimensional experience. There’s real depth of appeal in that engine, too. Get past the nasty augmented note in the cabin (how much better does the M4 CS sound without this unnecessary and horribly fake feature!) and it’s thrilling how you can really rinse it like crazy, using all the revs available as the head-up display glows angrily in the glass ahead. It may be turbocharged, but in this 331kW and 550Nm Comp Pack form it still has those special M genes, and not once do I question why its peak output doesn’t begin with a 6 or 7.

We take the cars out to the rather more remote areas of Wales, and swapping between the two is as fascinating as ever. There’s very little to choose between the outright pace of them – the C63 S covers the 0-100km/h dash in a claimed 3.9sec, the M4 two-tenths slower. Where the Merc punches hard with a furious fist of torque, so the M4 shimmies through a sequence of bends and stretches the gap a little more. But the BMW is more fun, more of the time. Whatever the combination of bumps, undulations and apexes, it remains unflustered, and once learnt, the idea of being greedy with the throttle and getting the tail moving around doesn’t seem as intimidating as it once did. It’s still a relatively large, weighty car to be mischievous with, and the turbocharged delivery will always be a little less predictable than an old, naturally aspirated straight-six, but you can forge that close relationship with it all the same. You can do the same, too, with the C63, although you’re more aware that if it goes wrong, it’s going to take a lot of broom work and a skip to clear up the mess.

Both cars feature strong brakes that remain untroubled by road driving, however spirited, but the BMW’s gearbox is snappier, more direct, even if its paddles could do with being more like the Alfa Giulia’s in their size and design. But I wish this car was a manual – it’d be so interesting to experience this engine and chassis with the simplification and added involvement of just six gears, manually selected.

Although I’ve grown to love the C63 S for a great many reasons, the M4 Comp Pack breezes this test just as it did last time. From being the unloved new boy to becoming polished elder statesman of the M family, we’ll miss it when it soon departs from the price lists. And maybe then, with a new M3/M4 that switches to all-wheel drive and a new straight-six based on the latest generation ‘regular’ engine, perhaps we’ll look back at this car more fondly, as a machine never truly appreciated while it was current, but that did possess ‘the right stuff’ all the same. Back to your beers, gentlemen, the fight’s over.

Mercedes-AMG C63 S Coupe
Engine V8, 3982cc, twin-turbo
Power 375kW @ 5500-6250rpm
Torque 700Nm @ 2000-4500rpm
Weight 1745kg
Power-to-weight 215kW/tonne
0-100km/h 3.9sec
Top speed 290km/h (limited)
Basic price $165,900

BMW M4 Competition Package
Engine In-line 6-cyl, 2979cc, twin-turbo
Power 331kW @ 7000rpm
Torque 550Nm @ 1850-5000rpm
Weight 1570kg (DCT)
Power-to-weight 211kW/tonne (DCT)
0-100km/h 4.1sec (DCT)
Top speed 250km/h (limited)
Basic price $156,529

Words: ADAM TOWLER
Photography: MALCOLM GRIFFITHS