Shoutout: BMW M4 Coupé CP vs. Mercedes-AMG C63 Coupé

When BMW first launched the M3, it may have underestimated the reverberation the model would have three decades later. The E30 generation version of the car has become the holy grail of genuine enthusiasts and keyboard warriors of the online automotive community. It inspires poetry, incites debate and much like the Volkswagen Golf GTI, is credited for creating a genre. Now fast-forward to the contemporary successor and things are a little different.

Due to different naming conventions, the two-door iteration of the M3 is now dubbed the M4. The physical dimensions — and perhaps the core essence of the vehicle — are far from what they would have been in 1985.

These attributes are arguably better fulfilled by the smaller BMW M2. No matter, it is what it is, and evolution is an unwavering part of the industry.

The fact remains that BMW has a pedigree in this ambit that Mercedes-Benz and Audi could only dream of. The ageing RS5 is something of a nonentity in this company. But when the Mercedes-AMG performance division launched the C63 Coupé in 2013, it provided healthy competition for the BMW M3 (E92) of the day.

Earlier this year, Mercedes-AMG released the follow-up and its arrival called for a duel with the Bavarian darling of the category. But surely, you ask, these products are merely less practical variations of their existing, four-door counterparts? There are technical differences between these cars and their sedan siblings. And certainly, enough difference to warrant closer evaluation in a comparison test.

We must also consider the demographics and requirements of the buyer who would opt for a coupé instead. Indeed, the virtues of dynamics, performance and of course, kerb appeal, hold more weight than practicality here.

For this challenge, Mercedes-AMG proffered a regular version of its C63. The more powerful S model was not available. BMW served up an interestingly-coloured unit of the M4, replete with the newly released Competition Package. Although it should be noted that even in this guise, its figures still do not match those of the contender from Stuttgart.

For the sake of transparency, we must also mention that the Bavarian car had been equipped with Michelin Pilot Sport Cup 2 tyres lifted from an M4 GTS. A puncture had disabled the rear left wheel and regular Pilot Super Sport rubber was not available. The Mercedes-AMG wore Continental Sport Contact 6 tyres.

As is the case with all our comparisons involving high-output machines, we summoned our resident track masters for their expertise. Volkswagen Motorsport series racing driver Mandla Mdakane and single-seater racer Ashish Narrandes undertook the lap-time challenges at Zwartkops Raceway in Centurion.

HEAVY METAL THUNDER:

Mercedes-AMG products feature an inherent brutishness. Large-displacement engines with menacing soundtracks and fearsome power outputs have defined the offerings from the division. Even the little A45 carries some of this spirit, despite having fewer cylinders than the bigger brethren. When we first sampled the new C63 in sedan guise we described the might from its engine as nuclear.

Bear in mind it is powered by the very same unit that does duty in the flagship GT, which succeeded the SLS. Adding a turbocharger might have muted some of the aural brilliance held by the old, normally-aspirated car. But this can be enhanced somewhat with an optional performance exhaust system.

Traction (or lack of) has always been a hot discussion point when it comes to the snarling products from Affalterbach. Some love the wayward, untamed nature of an AMG that is keen to slide its backside out on a whim. Others bemoan this slithery character. Well, pick a side, because the C63 coupé makes no apologies for its tendency to shimmy about.

In its most raucous Sport+ setting, it takes little to provoke oscillation. But on takeoff, once the rear tyres come to terms with being overwhelmed by all that power, boy, does it get going.

It seems every millimetre of pedal depression yields unfettered progress. That 120km/h is indicated near the bottom of the speedometer offers a clue to the velocities this car is capable of. Indeed, dispatching rapid cross-country sojourns is a forte of the C63.

And with Comfort mode engaged, it settles down into acceptable docility. Interior appointments are what you would expect on an upper-tier Mercedes-Benz product, with textured leather and classy embellishments. Although there are some bits that let it down: avoid the tacky piano black trim and white seat upholstery.

So as a powerful, relatively comfortable and charismatic touring machine, we heaped praise upon the coupé. But sentiments were different on the circuit. The model has a number of differences versus the sedan. A newly-developed rear axle is employed, which gives the vehicle a wider track.

The high negative camber of the wheels gives it a look that puts one in mind of a Deutsche Tourenwagen Masters racer. It features model-specific steering knuckles and the body has purportedly received extra reinforcement.

Drivers might notice a tangible difference sampling a coupé back-to-back with the saloon. But when assessed in isolation, it is not as close as you would like it to be, to the tenets of a focused track-slayer. Weight is an issue. This is a heavy car and our drivers commented on the sensations that occur when the vehicle transfers its heft under duress. Things can get unsettled quite swiftly should you find yourself being more brazen than usual.

This is notwithstanding the inclusion of a mechanical limited-slip differential, instead of an electronic unit on the more powerful S model.

However, there is ample grunt to connect the straight bits to the twisty ones. And on the corners, you may as well just give in to the indulgence of being able to go sideways. The coupé variant of the Mercedes-AMG C63 is thrilling to pilot indeed, even if it is a bit scary at times.

GREEN AND GOLD:

We will avoid the generational recap that often ensues whenever a review on the BMW M3 or M4 is published. You already know its predecessors were polished contenders that could fill volumes with acclaim. With the launch of the F30 generation model, the recipe changed most notably in the engine department. This is the first turbocharged iteration and the manufacturer is unlikely to go back.

With a meaty output, linear power delivery and a decent (albeit synthetic) sound, the switch to forced-induction in the M3 and M4 was forgiven. And with the optional Competition Package, BMW makes the prospect even more enticing. As you would expect, the first element of this extra kit is a spike in power. But that results in a frankly negligible difference when it comes to sprint times.

The biggest virtues of the Competition Package are constituted by the mechanical additions. Gains include new dampers, springs and anti-roll bars, in addition to revising the electronic rear differential as well as reconfiguring the various driving modes on offer. Weight-optimised alloys are part of the mix — plus a louder exhaust system, but that is drowned out by the noise of the lurid Java Green paintwork. Racier buckets feature inside, with cut-outs in the seatbacks that help alleviate back sweat.

It is all very appealing, especially to ardent BMW fans whose cupboards might house Motorsport-branded regalia. But is the Competition Package worth the additional outlay over a regular variant? In short, yes: the extra bits culminate into a driving experience that is markedly more cohesive and focused than you would get in a standard example.

This was noted particularly on our countryside test stints. In Competition Package specification, it relays a sense of greater tractability. The car feels better grafted-down and more enthusiastic when you seek to unravel its performance competencies. There are many positives about the level of body control it offers under pressure. We could still level criticism at the steering, however: even in Sport Plus mode, our racers quipped that more communication would be appreciated.

In any case, it took little time for the BMW to assert its superiority from a dynamic front. And it reinforced the notion that those Bavarians are skilled when it comes to producing a sporting machine that can be thrashed, lap after lap, without consequence. A comparatively lower weight held the M4 in better stead around Zwartkops. And this countered the disparity in power against the Mercedes-AMG. The BMW has less to lug around and this can be felt not only on the bounds of the circuit, but in daily driving conditions.

Where the C63 is thrilling and imbues one with the exciting sense one is on the ragged edge, the M4 offers a stark contrast. It inspires greater confidence, encourages easier exploration of the limit and feels livelier in a dynamic environment. But we probably should have expected that. It would be the predictable outcome given that BMW has had three decades to hone the recipe.

CONCLUSION:

Lending credence to our assertion that the BMW M4 Competition Package is the superior driving tool are the lap times. Would the C63 S derivative had made a difference? Not likely, with weight and traction being the biggest impediments to its success in this area. But at the end of it all, your decision will come down to preference.

The Mercedes-AMG offers enchantment with its sound and theatrics. It fares wonderfully as a cruiser as well. The BMW might not be as soulful in some regards, but it counters with an athletic fortitude that is beyond reproach. And is that not what an authentic performance coupé ought to be? – Brenwin Naidu (Pics: Waldo Swiegers)

Zwartkops Lap Times:

•BMW M4 Coupé (CP): 1:11.5

•Mercedes-AMG C63 Coupé: 1:13.7