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View all Mercedes-AMG A 45 reviews

The world's most powerful four-cylinder production car

Mercedes-AMG A 45 Hatchback (19 on)
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PROS

  • Plenty of grip on offer
  • Explosive performance from 2.0-litre engine
  • All-weather usability
  • Hard to keep up with on the road

CONS

  • Won't sound as exciting as rivals
  • Infotainment system not that intuitive
  • Ride will be firm compared with rivals
  • Hard to differentiate from A 35

PROS

  • Plenty of grip on offer
  • Explosive performance from 2.0-litre engine
  • All-weather usability
  • Hard to keep up with on the road

CONS

  • Won't sound as exciting as rivals
  • Infotainment system not that intuitive
  • Ride will be firm compared with rivals
  • Hard to differentiate from A 35

Mercedes-AMG A 45 Hatchback rivals

With the £35,000 Mercedes-AMG A 35 already squaring up to the likes of Honda's manic Civic Type R and the lovely Volkswagen Golf R, this A 45 S has a starting price tag of almost £50,000 puts it toe-to-toe with pricier offerings such as the covetable Audi RS 3 Sportback and BMW's entertaining M2 Competition.

You'd be hard pressed to tell the difference between A35 and A 45 S both externally or within the cabin, because almost all of the extra £15,000 has been spent on either magnificent mechanical wizardry or sock-it-to-me software add-ons to the infotainment system.

The former includes the world's most powerful turbocharged four-cylinder petrol engine in series production, and a sophisticated rear differential that extracts even greater levels of traction from the all-wheel drive system.

The latter appears to take the form of a demonstration by Mercedes' software boffins that throwing in the metaphorical kitchen sink is really no more than a starting point in relation to what's achievable with an already excellent infotainment system, and too much time on your hands...

One engine choice

No engine choice here; just the one. Not only does it set new benchmarks for four-cylinder performance, it's an absolute gem. 420hp and 500Nm of torque have been meticulously extracted from this hand-built 2.0 litre unit.

Mercedes A 45 S 2019 engine signed by Dennis Bogner

Mated to an eight-speed dual-clutch transmission with paddle shift override and all-wheel drive, this glorious sounding powerplant will shove the A 45 S to 62mph from a standstill in just 3.9 seconds and on to a top speed of 167mph.

You won't come across much of that torque below 3,000rpm no matter which of the seven available drive modes you select (and all you really need is a choice of Comfort or Sport+), but thereafter - with all the fabulous noises off you'd expect from such a highly-tuned unit - the hatchback takes off like a stabbed rat in any of the eight gears except the last: dropping out under the pressure of even a gentle motorway incline, eighth is really just a fuel-saving cruising gear.

Mercedes A 45 S 2019 drive mode selector

The gearchange is wonderfully smooth either left to its own devices or dictated to by the steering wheel-mounted paddles, and you'll have to be approaching the rev limiter in any gear to elicit even the slightest hiccup in proceedings.

AMG A 45 S turns up the wick

But what really sets the A 45 S apart isn't just the superb powerplant, but the extent to which you can deploy all that power courtesy of Mercedes' 4Matc+ rear differential, which houses a multidisc clutch adjacent to each wheel.

Mercedes A 45 S 2019 handling, yellow, cornering with lean

This allows the system to not only apportion drive between the front and rear axles - from 100% rear to 50/50 front and rear - but also up to 100% between the rear wheels.

And that equates to ridiculous cornering prowess. Inner rear wheel braking helps minimise understeer on the way in, and perfectly judged torque distribution allows you back on the throttle hilariously early on the way out, leaning on that outer rear tyre as hard as like without some much as a squeak of oversteer.

Though far from the last word in communication, the steering has a respectable heft to it, especially in Sport+ mode, and a little more feel than expected. It remains ruthlessly accurate at all times.

Mercedes A 45 S 2019 side, grey

Ride quality on British roads will become predictably tougher as you dial up the sportier settings in the selection of drive modes. Those of a loose-fillinged disposition may wish to opt for the B road safety of Comfort mode, which does at least offer a modicum of pliancy.

In all, the AMG A 45 S is destined to be faster, and braver, through the bends than most who will own it. An absolute riot.

Subtle interior differences for A 45 S

A relatively low-key upgrade to the standard A-Class interior rewards the A 45 S with sportier seats and attendant go-faster stitching, a slice removed from the bottom of the steering wheel, twin 10.25-inch screens perched on the dashboard in lieu of a proper driver's instrument binnacle, and a scattering of AMG badging.

Mercedes A 45 S 2019 driving position

All is classic Mercedes and feels acceptably well screwed together, yet, given the amount of switchgear that's been transferred piecemeal to menus within menus on those twin screens, it's surprising to note how many knobs and knockers remain dotted hither and thither. And, indeed, how often control switchgear is duplicated...

The diminutive thumb-operated track-pad type controls mounted on the steering wheel will prove vexing for those brought up on a diet of Mercedes' more tactile, accurate and intuitive roller switches, while the absence of a proper switch to instantly disengage the ghastly lane keeping assistant without wading through menus is a disaster.

Shame, really, that a fine infotainment system with terrific graphics - clearly visible even in bright sunlight - should become so over-planted with because-we-can superfluous software trees as to often make the wood nigh-on invisible.

Mercedes A 45 S 2019 front seats

There have been gripes about the setting of the AMG A 35's driver's seat too high, but the A 45 S seems to suffer from no such problem. The sports seat is snug and extremely comfortable, with excellent lateral support. Ergonomics are largely outstanding, though it would be good if the steering wheel adjustment allowed the helm to be lowered a little more.

There is, alas, no Jesus handle atop the door frame for the front passenger to cling onto when lateral G rises, and the rear seat passengers, though they won't lack for either head or legroom, must suffer the same misfortune exacerbated by far less lateral bolstering to their seats. Given this car's cornering abilities, this seems an odd oversight.

Read more:

>> Fancy the slightly less hardcore A 35 version? Read all about it in the full A-Class review

>> How does the A 45 compare with our reigning hot hatch champ, Ford's Fiesta ST?

Mercedes-AMG A 45 Hatchback rivals