Australia is currently on the receiving end of two Mercedes-AMG models featuring the world’s most powerful production turbocharged four-cylinder engine. The Mercedes-AMG W177 A45 S 4Matic+ and the C118 CLA45 S 4Matic+ are currently on sale, priced at $93,600 and $111,200 (before on-road costs) respectively.
“We have completely redesigned our 45 models – from the engine and transmission through the chassis, the elaborately constructed drivetrain to the body structure and of course the design itself – all with one goal: to raise vehicle dynamics and the sporty driving experience to a level previously unimaginable in the compact class,” said Tobias Moers, CEO of Mercedes-AMG GmbH.
At the heart of the duo sits a fire breather, which Mercedes-AMG calls “a milestone achievement”. This powerplant is capable of producing 310kW of power and a scarcely believable 500Nm of torque. The 2.0-litre M139 block – which is the successor of the M133 – now has its twin-scroll turbocharger behind the engine for better air flow management rather than the M133’s front-mounted setup.
Speaking of the turbocharger, the ‘45 S’ duo’s compressor makes up to 2.1 bar’s of boost, which is a lot. That said, the exhaust valves on the M139 are bigger than before and has a higher compression ratio to accommodate the added boost. This allows the engine to achieve an output per litre of 155 kW, which is better than what most super-sports car engines can do, says the brand.
The immense power on tap means the CLA45 S can sprint to 100km/h from standstill in just 4.0 seconds, while the A45 S does it one-tenth faster. This is partly thanks to the 8-speed AMG Speedshift DCT 8G dual-clutch transmission that “has been configured for spontaneous acceleration in all speed ranges”. A plethora of driving modes and electronic wizardry is also to thank, such as the Race-Start launch control function. The computer-controlled power is then channel to all corners via the brand’s 4Matic+ system with AMG Torque Control in the new rear differential.
We’ve established that the ’45 S’ duo are more than just quick, but how well do they scrub off that speed? Both models receive a 6-piston calliper setup on both ends of the front axle that squeezes a pair of 360mm rotors. Meanwhile, each end of the rear axle gets a single-piston calliper which bites down on 330mm discs. The discs themselves are internally ventilated and cross-drilled to better dissipate heat and prevent fading, even with extreme use, and the brake callipers are painted red with the AMG logo in black.
The exterior of the A45 S 4Matic+ receives an AMG-specific radiator grille, wider front wings or fenders with flared out wheel arches and a front apron featuring a “jet-wing” design. The rear-end is finished off by two pairs of 90mm tailpipes with AMG lettering and a diffuser with two vertical fins.
The CLA45 S 4Matic+, with its wider front track “has a naturally self-assured stance and does not require the same frontal flares as the A 45 S 4MATIC+” said the automaker. However, it does share the same radiator grille as the A45 S. However, the rear sports a diffuser with four vertical fins, and a boot-lid mounted spoiler.
Inside, the MBUX infotainment from the latest A-Class has been given AMG-specific graphics and displays including a race timer, G-meter as well as engine and telemetry data. It also gets something called AMG Track Pace which is a racetrack-specific virtual race engineer that can continuously monitor more than 80 vehicle-specific data points. It also displays lap and sector times, as well as the respective difference from a reference time, the company said.
Standard features for both models include a Burmester stereo system, an AMG Performance steering wheel, heated and electrically-operated sports seats finished in two-tone leather with contrasting yellow topstitching, brushed aluminium trim, Keyless-Go and start, ambient lighting featuring 64 colours, dark-tinted privacy glass and a panoramic glass sunroof.
In terms of safety, the duo gets the Driving Assistance Package Plus, Active Distance Assist Distronic (including Cross-Traffic Assist), Active Lane Change Assist, Parking Package featuring 360° camera and MULTIBEAM LED headlights with Adaptive Highbeam Assist Plus.