Why did Mercedes-AMG develop its 2.0-litre 4-potto produce near-ludicrouspeak outputs of 310 kW and 500 Nm? Well, so that the enginecould power the flagshipof the W177-generation A-Class, which (again) moves performance goalposts in the "hyperhatchback" segment…We headed to the ex-F1 Jarama circuit in Spain to samplethe A45 S.

What’s new?

First shown at the recent Goodwood Festival of Speed, the A45S is the first 45-seriesMercedes-AMG to be spun from the new A-Class. The A35 has had a month or 2to shine, but now it’s time for the real McCoy to grab the limelight, which few would argue it doesn'tdeserve. The headline news is that the newcomer's2.0-litre 4-cylinder turbopetrol developsno less than 310 kW and 500 Nm of torque. Those numbers see the Benz leave the hot hatchbrigade well in its wake and move towards the realm of the hyper hatch;its an engineeringachievement that beggars belief.

Don't confuse this with the A35, this one gets the full Panamericana grille.

The A45 S –the only version of the W177A45 hatchback that will be released in South Africa–has undergone a raftof improvements to optimise itshandling, performance and even comfort. It doesn’t appearto be all about statistics and numbers with this version, either:Mercedes-AMG seems to haveendeavoured to transform the A45 from an electronically-aided marvel to more of a driver-focused machine. Has Affalterbach succeeded?

Have a read of our A35 launch review here

Engine wizardry

The A45's potent powerplant is nothing short of a gem; it's positioned differently to the comparatively mild2.0-litre motor in the A35 (turned by180 degrees,with its turbocharger and exhausts at the back and the intake facing towards the front bumper). This configuration aidsaerodynamics and shortens piping distances. The twin-scroll turbocharger has been cranked up to boost to 2.1 bar (it’s where the bulk of the performancegaincomes from), while new roller-bearings within the turbo's internalsallow it to spin up faster and reach optimal pressure sooner, which reducesturbo-lag.

In action, the enhancements prove… extremely effective!The responsiveness and immediacy of power delivery when exiting corners with the A45 S is quite unlike any turbocharged petrol engine that I’ve driven to date (well, at least ones without electric assistance). The motor easily spools up to 7 200 rpm, where the acceleration sensation just starts to taper, before you summon the next gear and the surge repeats with renewed brute force.

Intake at the front exhausts at the back, it's turned 180 degrees compared to A35.

The engineers have attempted to give this engine a unique soundtrack and the way they've gone about itis the product ofa fair bit of hocus pocus. The sound is conjured up through a combination of exhaust flaps that open up as well asspecial engine sensors that pumpactual engine sound into the cabin. When out on the road, short bursts of acceleration makethe A45 S soundbeastly, really raspy and loud, much like you’d expect from a shouty hatchback with flared arches, a front splitter, rear diffuser and 4exhaust ends. On track, when you’re on maximum throttle for long periods, it’s a bit droney and tiresome, but come off the throttle(while in Sport plus or Race mode) and it'll rattle off a hilarious volleyof cracks and backfires.

All of this translates into some manic acceleration times, as you mayimagine. If you utilise launch control in Race Mode,the A45 S will propel itself from 0 to 100 kph in a ballistic 3.9 seconds –it marksthe first time one of the GermanBig 3(Audi, BMW and Mercedes-Benz) officially claim to scrape under the 4-second barrier with acompact performance model. The 8-speed dual-clutch ‘box fires though shifts with the ferocity of an '80s headmaster’s cane. Downshifts are met with rev blips, but are engaged with alarming speed, especially when using the manual paddle shifters.

Mercedes-AMG will launch the A45 S and CLA45 S during Q4 of 2019.

Is it good to drive?

Okay, so the original A45 had a few issues, many of which we've reported on. Its ride qualitywas overly rigid (almost bouncy at times) and it wasn’t very involving to pilot– the whole driving experience seemed to revolvearound the front differential helping to steer the carout of corners.

Fortunately,the new A45 S represents a vast departure from its predecessor in terms of its general demeanour. The newcomer'sbody is admittedly fundamentally stiffer and its suspension is still taut, but not in a way that it jolts its occupants around or skips across uneven surfaces. Out in the hills around Madrid, the roads wind for tens of kilometres;they're perfect for getting into a rhythm and assessing the nuances of the new A45 S’handling talents. The front end bites more than before, reducing some corner-entry push and increasing agility when changing direction. It still requires soft, guiding inputs to alter direction, more so than in hot hatches like a Fiesta ST or Megane RS, whichcan be "thrown about"merrily, if at lower speeds.

The ride is much-improved from the bumpy and crashy previous generation.

Much of the improved handling can be attributed to the talents of the A45 S' new differential, which can divert torque to individual rear wheels, where before it could only send it foreor aft. To put it another way: you can now achieve power-on oversteer in anall-wheel-drive hatchback. The Jarama circuit starts with 3 alternating slow-speed hairpins and with the bitier front-end you can snap up an apexand then bury the throttle early. Instead of boring understeer (so characteristic of AWD hatches) the rear actually starts to come around in a controlled easy-to-catch slide. It adds another, unexpected, element to driving the A45 S. Previously, it lacked thedriver engagement of the rear-wheel-driveBMW M2,but nowthere’s something less predictable about going fast in the flagship A-Class. It's also equipped with a Drift Mode, whichadaptsthe ESP to facilitate power slides.

If the slidey stuff doesn’t interest you, simply slip the drive mode back into Sport or even Sport Plus and let that confidence-inspiring4Matic all-wheel-drive system ensurethat all 4 corners of the A45 S remainin check/solidly-gluedto the road. The steering deservesmore credit than most electrically assisted setupsfor providing good feel and feedback;although it weights up artificially the more angle you apply, it feels quite natural.

Take a look at the CLA 45 S here.

Performance add-ons

The A45 S interior can be specced with yellow stitching, stripes and an Alcantara wheel.

There are notable changes to the interior. Keenly-eyedobservers will note the rotary dial within the steering wheel and the adjacent toggle buttons. The rotary dial deals with the driving modes, making it easy to scroll through modes without having to peerat the transmission tunnel. The toggle buttons on the left allow for transmissionadjustments, exhaust loudness, suspension setup and traction control settings. It’s a clever, uncomplicated solution, but it feels plasticky to touch where it could have been rubberised or even metallic. The iffy finishlets down an otherwise intuitive design.

Meanwhile, onboard data logging is becoming a must-havefor modern performance cars. Evidently, some owners don't only want to flailand cane theirperformance machines onracecircuits; they want to record electronic records to provetheir track workand compare their lap times (and other herculean feats achieved by their cars, such as g-force) with other drivers.The AMG Track Pace system tracks all performance telemetry, which you candownload to your phone/computer for closerinspection later on. It will also sync video footage to the telemetry if you use your phone’s camera.

This steering-wheel-mounted dial lets you quickly scroll through driving modes. It feels a bit too plasticky to operate, however.

As for the quality of front-passenger accommodation, the Mercedes-AMG single-piece man-made leather sports seats are comfortable and offer ample lateral support. The sporty ambience is heightened by the flat-bottomed steering wheel covered in dimpled leather. This can be upgraded to Alcantara at extra cost and there’s the option of adding yellow stripes to the seats, steering wheel and centre-console stitching. It ups the sporty atmosphere in the cabin, but, as with most of Benz’s current A-Class derivatives, the fit-and-finish and material choices could be more luxurious.

Summary

Overall the A45 S feels more engaging to drive than its immediate predecessor, which was already a very rapid car.

Whereas the Mercedes-AMG A45 S'predecessor was a potent performer, it proved a bit of a blunt instrument when driven on a track. By contrast, the new more powerful and, therefore, faster W177 versionoffers much-improved dynamics, rides less harshly on public roads and is betterto drive on an everyday basis. On a track (with Race Mode engaged) you can play around with the rear end under power while the front- is more eager to turn in. Plus, the new differential adds an extra dimension to the A45 S it didn’t have before –drift mode should facilitate raucous fun on askid pan.

Tosum it all up, the newcomer'sengine is a technological masterpiece. Itsomehow produces tremendous outputs while all-but-banishingboost lag from itsturbocharged setup. As a whole, the A45 S feels more engaging to drive and more of a driver’s car than ever before. Qualms about interior qualityaside, this AMG is wholly better than its predecessor and deserves a seat at the head of the table in the battle for hyper-hatch supremacy.

Related content:

2020 Mercedes-AMG CLA 45 Goes Official

New Mercedes-AMG A45 for SA in 2019

Track Race: Audi RS3 vs Mercedes-AMG A45

Drag Race: Audi RS3 vs Mercedes-AMG A45

Drag Race: BMW M2 vs Mercedes A45 AMG [Video]