MADRID, Spain - Any discussion on the Mercedes-AMG A45 S is inevitably peppered with hot hatch superlatives: its new 2,0-litre powertrain is the world’s most powerful series-production four-cylinder engine; its claimed 0-100 km/h sprint time dips under four seconds; it could cost more than a million rand when it launches in South Africa in October…

Whether it will justify a seven-figure price tag is a question too subjective to answer without road-testing the vehicle on local soil. What I can tell you right now is the new 310 kW engine (that’s 155 kW per litre) does, in fact, feel heroically muscular. Allied with the traction afforded by the 4Matic+ all-wheel-drive system, which distributes torque between the axles and the rear wheels, 3,9 seconds sounds like an entirely plausible figure (although entirely other-worldly, too – this is a midsize hatchback, after all).

We completed five laps of the 3,85 km Jarama Circuit north of the Spanish capital, Madrid, in an A45 S and CLA45 S each and that allowed us to test the various drivetrain settings in the jumbled collection of curves; extend the legs of the powertrain down the long straight; and get a real feel for the 350 mm front/330 mm rear braking system. We then embarked on an extended drive on empty (in the 40-degree heat, it was siesta time for most Spaniards) country roads further north. If there were any chinks in the A45 S’ armour, the complex track layout and undulating passes would expose them.

Let's back up a bit...

Revealed in 2013 to much whoopla about, you guessed it, the world’s most powerful series-production four-cylinder (265 kW), the original A45 quickly asserted its dominance among hot hatches. As is their habit, however, the German brands engaged in a ruthless power war and Audi finally unleashed an RS3 with 294 kW, besting the facelifted AMG A45’s figure by 14 kW.

You’d therefore not be surprised to read the new A45 S (there’s a standard 285 kW model, too) boasts a nicely round 310 kW. That’ll be a tough figure for its German rival to beat, even if the RS3 retains the 2,5-litre, five-cylinder engine. Perhaps more telling of the A45 S’ day-to-day character, however, is the stout 500 N.m of torque, and how it’s delivered. Where other turbocharged engines offer as wide a torque spread as possible, often at the cost of top-end fizzle, the A45’s maximum output is developed high in the rev range across just 250 r/min. The headline 310 kW figure, meanwhile, kicks in at 6 750 r/min and the engine revs to a heady 7 200 r/min.

Transferring this significant amount of twist to the 19-inch wheels (wrapped in 245/35 rubber) is a newly configured eight-speed dual-clutch transmission promising quicker shift times than the outgoing seven-cog unit.

Suspension-wise, the 45-series utilises a MacPherson strut arrangement up front, with a four-link layout aft. AMG Ride Control damping is standard and can be toggled between comfort, sport and sport+ (with three further programmes – slippery, individual and race – on offer). Likewise, the ferocity of the exhaust system can be changed between balanced or powerful; the ESP system offers tweaks between basic, advanced, pro and master; and the response of the engine has its own four settings. It’s a bit befuddling at first acquaintance but, thankfully, an AMG-specific display within the MBUX system shows you at all times which parameters are set to which mode.

Tackling the circuit

Which did I choose? Well, initially, I set out on Jarama in sport mode, which strikes a fine balance. Set so, the hatch demonstrates deft body control, leaning ever so slightly into the longer sweeps, the front suspension compressing a touch under heavy braking and the rear-end gently edging aside when booting it out of a tight corner. The steering, however, feels too light in sport and doesn’t weigh up much when the tyres start encroaching on their traction limits.

Best to turn the new steering-wheel-mounted dial to sport+, which sharpens the throttle even more and firms up the suspension and steering. Here, the tiller has sufficient heft to work against (although real feel is still absent), the suspension retains enough compliance to suggest this mode is usable on-road, and the throttle is sensitive without resorting to the hair-trigger effect of some AMGs in sport+.

I must mention the brakes here, which are some of the best on any sportscar. The stoppers bite firmly right at the top of the brake pedal’s travel and the four-piston monobloc front callipers and single-piston floating unit at the rear repeatedly slowed down the press cars without detectable fade (generally a given at track-based vehicle launches). They’re hugely confidence-inspiring.

Our stint on Jarama complete, we received a passenger-seat demo from an AMG chassis fundi on the vehicle’s “drift” mode, which is activated in the race driving mode by disabling ESP, switching the transmission to manual and tugging both shift paddles. It’s not really a drift mode – not in the sense that only the rear wheels propel the vehicle – but it uses torque-apportioning to get the rear-end sideways. Holding a slide is impossible (there’s simply too much traction) but it’s a fun feature nonetheless.

And then Spain's country roads

Lunch barely held down, we set off for Spain’s glorious regional roads. Whoever chose the launch route deserves a promotion because it included some of the best passes I’ve driven. There were switchbacks aplenty; stretches of clearly sighted bends; climbs and dips; and only a sprinkling of cyclists. And the A45 S shone. The ride is unquestionably better than on the old model. While still firm, there’s adequate compliance in the more benign driving modes to suggest the little AMG should work well on our patchier surfaces. The overly light steering, meanwhile, bothered me less and I appreciated the engine’s razor-sharp response to throttle inputs; the dazzling composure under heavy braking, even mid-corner; and the eight-speed transmission’s speediness, in stark contrast to the previous unit’s occasional obstinance.

Question time, then: how does the A45 S compare to the RS3 (and the BMW M2 to the CLA45 S)? Certainly, the Audi has the more characterful engine – the AMG’s is loud but monotonous – and it feels as potent. I’d give the advantage in terms of perceived quality to the Audi, too. While the AMG’s interior looks great, some plastics (the door handles, for example) feel basic at potentially seven figures. The Mercedes, however, has the superior chassis, resisting understeer better than the Ingolstadt-based brand’s offering.

The BMW, meanwhile, is unique in offering a playful rear-wheel-drive platform and its M3-derived inline-six engine is fantastic. The cockpit, though, feels its vintage and, when you’re not in the mood, the coupé can be hard work.

Perhaps of more importance to Affalterbach fans is that AMG’s engineers have managed to broaden the scope of the A45, imbuing it with more refinement while elevating its performance and making it more fun to drive. It feels like a product of the same stable as such lairy models as the C63 S and GT, and that fact alone may go further than you’d think to justify a potential seven-figure price tag.



FAST FACTS

Model: Mercedes-AMG A45 S 4Matic+ 8G-DCT
Price: TBA
Engine: 2,0-litre, 4-cyl, turbopetrol
Power: 310 kW @ 6 750 r/min
Torque: 500 N.m @ 5 000-5 250 r/min
0-100 km/h: 3,9 seconds*
Top Speed: 270 km/h*
Fuel Consumption: 8,3 L/100 km*
CO2: 189 g/km
Transmission: 8-speed dual-clutch
Maintenance Plan: Five-year/100 000 km