Dawn of the hyper-hatch

By Ghaith Madadha - Sep 08,2014 - Last updated at Sep 08,2014

Leading from the forefront of a new era of extreme 300BHP+ hatchbacks, the Mercedes-Benz AMG A45 is the world’s most powerful hatchback, whose 355BHP turbocharged four-cylinder engine is the most powerful regular production engine of its size.

A highly tuned version of Mercedes’ new full-size A-Class premium brand hatchback, the AMG A45 and its 316BHP BMW M135i and 296BHP Audi S3 cohorts are a post-hot hatch segment, more accurately described as hyper-hatchbacks.

Elegant and restrained with few telltale signs of its brutal potential, Mercedes’ driver-focused high tech hyper-hatch however features a sportily luxurious cabin, and is expected to be joined by a slew of similarly powerful rivals including the Ford Focus RS and Volkswagen Golf R400.

One would usually refer to a featured car’s predecessor for context, but the tamer first generation Mercedes A-Class offered nothing remotely similar to the AMG A45. The last truly compact hot Mercedes — the 1988-93 190E 2.5-16 ‘Cosworth’ saloon — was also a different animal, with high-revving naturally-aspirated four-cylinder, rear-wheel-drive and manual gearbox, rather than turbo four-cylinder, four-wheel-drive and dual-clutch automated gearbox.

Mercedes’ in-house AMG tuners’ first transverse and four-cylinder offering, the A45’s engineering concept owes more to rally-bred turbocharged four-wheel-drive compacts like the 1986-93 Lancia Delta Integrale, and the Mitsubishi Lancer Evo and Subaru Impreza WRX STI. In execution, the A45 is of a contemporarily urbanised milieu where compact and fuel efficient premium brand cars are gaining currency.

Prodigious four-pots

A prodigiously powerful and small brute with high 1.8-bar boost pressure, the AMG A45’s turbocharged 2-litre four-cylinder develops 355BHP at 6000rpm and 332lb/ft throughout 2250-5000rpm, with high 178BHP/litre power density on par with the most exotic supercars. With twin scroll turbocharging technology and short intake manifold, the A45 well-minimises low-end lag typical of turbo engines.

Spooling up quickly, and with four-wheel-drive traction, the AMG A45 is rapid off-the-line, and with driver pinned back in seat, blasts through the 0-100km/h benchmark in scant 4.6-seconds and tops out at an electronically-limited 250km/h. Driven on the Yas Marina Formula One circuit in Abu Dhabi, the speedometer needle keeps climbing with little-abated ferocity to over the 200km/h mark.

Once spooled up and in its vast mid-range maximum torque band the A45 pulls confidently hard, and deliver effortless versatility and brisk overtaking. Hugely powerful, the A45rarely requires one to delve further than 4000rpm for brisk daily driving.

However, power accumulation starts welling up by 3000rpm, and underwritten by massive torque, transitions to a fervent power surge as it’s rev counter tears through to a maximum 6700rpm.

At its best when loaded against a steep incline, the A45 pounces uphill with disdainful ease and eager ability. Punchy and responsive, the A45’s intensely powerful engine treats one to an aggressive soundtrack of distant turbo whine and wastegate hisses and aggressive flutters at high rev lift-off and up-shifts.

Tenacious traction

Driven through a 7-speed automatic gearbox tuned similar to the Mercedes AMG SLS GT, the A45 can be driven in more aggressive ‘sport’ and ‘manual’ shift modes, using the steering-mounted paddle-shifters. Able to automatically interrupt ignition and injection for quicker up-shifts at full load, the AMG’s surge of power is thus little interrupted.

Under normal conditions the AMG A45 drives the front wheels but can channel its ferocious power through all four wheels if slip is detected. Using a rear axle-mounted clutches, the A45 can divert up to 50 per cent power to the rear wheels when needed, while a torque vectoring system brakes the inside rear wheel to prevent wheel-spin and mimic a mechanical limited-slip differential.

Possibly and potentially the best of many cars driven through a particularly demanding and often used favourite Jordanian driving route, the A45’s sure-footed grip, massive power and quick precise steering made short work of fast winding hill-climbs, while its agility and four-wheel traction came in handy through steeper but much narrower segments.

Through snaking cross-country sections with elevations, descents, sudden dips and crests and a combination of rough, smooth, new and old tarmac, the AMG A45 was thrillingly composed, quick and capable.

Pouncing from one corner to the next at brisk pace and superb control, the AMG A45’s huge ventilated and perforated disc brakes provided tireless and curt stopping ability when approaching tight bends.

Corner carving

Hugely entertaining, rewarding and swift through cross-country switchbacks, the AMG A45 is at its best through such roads when driven with a deliberate, involved and meaningful manner. Braking and downshifting on approach, one best takes a corner by turning in early and succinctly to avoid the heavier front-end from going wide. Done so, the A45 grips hard into a corner while the rear-end is encouraged to attempt a sideways flick, which aided by inside wheel braking turn tightens the cornering line.

At this point reapplying the throttle by the apex sends power to the rear wheels and the A45 digs its heels and blasts out onto the straight, ready to repeat the process as required.

A car that rewards meaningful driving, the A45’s slim low profile 235/35R19 tyres grip tenaciously and its firmly tight suspension brilliantly controls body weight shifts when one leans in and loads up the outside wheels through corners, but when driven in a sloppy or half-hearted manner, the A45’s stability and traction controls watchfully tidy up inadvertent rear-end slippage caused by power surge when tyres aren’t loaded up through a corner.

Stable, planted and reassuring at speed, the A45’s suspension and optional 19-inch alloy wheels ride firm — for Jordan, 18-inch standard wheels would be more forgiving. Though firm, the A45 however feels buttoned down, even on choppy roads, where it bobs somewhat but doesn’t uncomfortably jounce sideways.

Practical performance

A sportier, more conventional and hunkered down hatchback design than its upright predecessor, the new A-Class elegantly translates Mercedes’ design language and identity for a more youth-oriented hatchback. With sporty grille-mounted tri-star, aggressively wide intakes, road-hugging front bumper and side skirts, and massive alloy wheels, the A45 performance version has a discretely athletic sense of road presence.

However, the optional Edition 1 package is anything but discrete, with extrovert graphics, side winglets and massive tailgate-mounted wing to match the AMG A45’s extreme performance.

Sporty and stylish inside, the A45 features red-stitched leather sports seats, red-ringed round crosshair air vents, chunky flat-bottom steering wheel, un-laminated carbon-fibre dashboard and user-friendly layouts including clear instruments and tablet-style infotainment screen.

A daily-use high performance machine, the AMG A45 is a practical 5-seat 5-door hatchback, with fold-down rear seats expanding its 341-litre boot. Normally available with tyre-repair kit, Jordanian-spec versions get a full-size spare tethered in the boot, but this reduces luggage room. Highly adjustable seats and steering provide excellent driving position with decent visibility, but adjustable front headrests would be welcome.

Manoeuvrable and compact, the A45 returns good 6.9-7.1-l/100km fuel efficiency when driven for economy, and features auto stop/start in ‘comfort’ drive mode. Creature comforts include remote central locking, climate control, parking assistance and USB/Bluetooth compatible sound system.

Extensive safety kit includes numerous airbags including knees and windows, adaptive main beam and Collision Prevention Assist system.

TECHNICAL SPECIFICATIONS

Engine: 2-litre, turbocharged transverse 4-cylinders

Bore x stroke: 83 x 92mm

Compression ratio: 8.6:1

Valve-train: 16-valve, DOHC, direct injection,

Redline: 6700rpm

Maximum boost: 1.8-bar

Gearbox: 7-speed automatic, four-wheel-drive

0-100km/h: 4.6-seconds

Top speed: 250km/h

Redline: 6700rpm