Agile and safe on country roads, ultra-dynamic on the racetrack: The Mercedes-Benz A 45 AMG presented in 2013 exceeded all expectations, and immediately captured the top position in its market. Nonetheless, this worldwide success is no reason for the sports car brand within Mercedes-Benz to rest on its laurels. On the contrary, for after extensive updating the Mercedes-AMG A 45 4MATIC now guarantees even more emotional appeal and driving pleasure. With a peak output of 280 kW (381 hp) and maximum torque of 475 newton metres, the turbocharged AMG 2.0-litre four-cylinder engine once again comes top in the competitive line-up. The revised transmission ratios, aerodynamic fine-tuning and the new DYNAMIC SELECT driving modes familiar from the Mercedes-AMG GT raise performance to an even higher level. Driving dynamics can be further enhanced with optional extras in the guise of the AMG RIDE CONTROL sports suspension and the AMG DYNAMIC PLUS package.
The entry by Mercedes-AMG into the compact class, and therefore a completely new market segment, in 2013 was a brave move. But it has proved more than worthwhile: within a very short time the compact AMG models have been an impressive success story. The sporty and exciting driving experience plus an emotionally appealing design immediately impressed the dynamic and individualistic target group, and gained new customers for the sports car brand.
And Mercedes-AMG is still going full-throttle: “We never rest on our laurels, but constantly strive to develop our products further,” says Tobias Moers, Chairman of Mercedes-AMG GmbH. “The A 45 still had so much improvement potential that we felt compelled to realise it to the full. Our brand claim simply obliges us to.”
Accordingly the development team at AMG carefully scrutinised every detail of this compact best-seller, whose designation Mercedes-AMG A 45 4MATIC follows the new nomenclature, and applied improvements wherever thorough examination found them to be appropriate for further increases in driving dynamics and enjoyment. The result is certainly impressive, and above all tangible when sitting at the sport steering wheel offering great grip: “We have further refined our turbocharged four-cylinder to develop 280 kW (381 hp) and 475 newton metres. This means that the Mercedes-AMG A 45 remains the world’s most powerful and dynamic compact sports model,” says Christian Enderle, Head of Engine and Powertrain Development at Mercedes-AMG.
But that is not all. Modifications to the transmission, suspension, electronics, design and appointments have turned the compact sports model into a completely new car: In no other model in this class is true motor racing spirit so obvious as in the Mercedes-AMG A 45.
The power upgrade has lifted this extremely sporty compact into dimensions previously the province of higher vehicle classes: 100 km/h is already reached from a standstill in 4.2 seconds. This means that the new A 45 accelerates 0.4 seconds faster than its predecessor. At the same time, its exemplary fuel consumption has been kept at the level of the previous model: no other high-performance model in this class can match its NEDC fuel consumption from 6.9 litres per 100 kilometres (corresponds to 162 g/km CO2).
The data at a glance:
| Mercedes-AMG A 45 4MATIC | |
| Displacement | 1991 |
| Bore x stroke | 83.0 x 92.0 |
| Output | 280 kW (381 hp) at 6000 rpm |
| Peak torque | 475 Nm at 2250-5000 rpm |
| Power-to-swept-volume ratio | 141 kW (191 hp) |
| Fuel consumption NEDC combined | 7.3-6.9 l/100 km |
| CO2 emissions | 171-162 g/km |
| Efficiency class | D |
| Emissions standard | EU6 |
| Acceleration 0-100 km/h | 4.2 s |
| Top speed | 250 km/h* |
* electronically limited, top speed can be optionally increased to 270 km/h only in conjunction with the AMG Driver’s Package
The extremely agile, turbocharged four-cylinder engine combines its exhilarating power and exemplary efficiency with another top attribute: the output of 141 kW (191 hp) per litre marks a record for a series production four-cylinder engine, and raises the high-performance AMG power unit to the level of thoroughbred super sports cars.
The engine specialists at AMG mainly achieved this increase in power output with a newly configured valve assembly. In addition the combustion processes have been optimised by reconfigured timing and turbocharging. The maximum charge pressure continues to be 1.8 bar.
AMG 2.0-litre turbocharged engine with numerous high-tech components
The high-tech features of the turbocharged four-cylinder engine from Mercedes‑AMG include spray-guided direct petrol injection. Piezo injectors centrally located in the four combustion chambers inject the fuel at a pressure of up to 200 bar. The combination of multiple fuel injection and multi-spark ignition improves fuel economy and significantly increases thermodynamic efficiency, leading to low exhaust emissions. The twin-scroll turbocharger and maximum dethrottling of the exhaust system improve the charge pressure build-up, and therefore the engine’s response to the accelerator.
Other highlights include: gravity sand-cast all-aluminium crankcase, weight-optimised crank assembly with forged steel crankshaft and forged pistons with friction-optimised piston rings, NANOSLIDE® cylinder wall technology, alternator management and ECO start/stop function. Sophisticated cooling of the engine oil, coolant, charge air and transmission fluid not only improves durability, but also suitability for the racetrack.
The trailblazing technologies and outstanding attributes of this high-end four-cylinder have also elicited the highest praise from independent experts: in 2014 and 2015 the AMG engine received the coveted “International Engine of the Year” award in the 1.8 – 2.0 litres displacement class.
High torque, great flexibility and an emotional engine note
On the road the turbocharged AMG 2.0-litre four-cylinder engine thrills with extremely fast responses to accelerator movements, high torque, enormous flexibility and an emotional engine note. The exhaust system features an automatically controlled exhaust flap as standard. The intensity of the engine note changes according to the currently active AMG DYNAMIC SELECT driving mode. The sound has also been generally refined and perfected.
From the GT and C 63: the new AMG DYNAMIC SELECT driving modes
Already familiar from the Mercedes-AMG GT sports car and the top C-Class model, the Mercedes-AMG C 63, DYNAMIC SELECT now also allows the widest possible selection of driving dynamics in the Mercedes-AMG A 45. To this end the four modes of “Comfort”, “Sport”, “Sport +” and “Individual” are available for selection. The modes are selected using the AMG DYNAMIC SELECT Controller, and modify parameters such as the engine and transmission characteristics. The Controller is positioned in the centre console, behind the selector lever for the AMG SPEEDSHIFT DCT 7-speed sports transmission.
“Comfort” mode allows consumption and comfort-oriented driving with a subdued engine note and gentle gearshifts. The ‘sailing’ function installed for the first time helps to save fuel by decoupling the engine from the powertrain as soon as the driver releases the accelerator within a speed range of 60 to 160 km/h. In Comfort mode the ECO start/stop function is also active, switching the engine off automatically whenever the vehicle stops for a longer period.
“Sport” mode emphasises agility and driving pleasure, with a sporty engine and transmission configuration. The sound of the turbocharged engine becomes more throaty. The ECO start/stop system and the sailing function are inactive.
In “Sport +” mode the power transmission reacts even more immediately. The shift strategy of the transmission is optimally modified for the needs of a very sporty driving style – including extremely short shift times, emotional double-declutching and faster responses to the accelerator. Partial cylinder suppression by means of a momentary and precisely defined retardation of ignition and injection under full throttle speeds up the gear changes, and is also audible to the driver.
Over and above the preconfigured modes, the “Individual” driving mode makes it possible to vary individual parameters for the engine, manual or automatic transmission mode and 3-stage ESP®.
All DYNAMIC SELECT modes are also visualised in the cockpit display. The driver sees a special icon and corresponding information in the central display of the AMG instrument cluster. A pop-up window also appears on the free-standing central display whenever the transmission mode is changed: depending on the mode, the animated Mercedes-AMG A 45 is shown with an appropriate graphic and colour presentation. While subdued shades of blue predominate in “Comfort”, the car is shown on a racetrack in “Race” mode (included with the optional DYNAMIC PLUS package or the AMG RIDE CONTROL sport suspension – including red/white kerbs.
The AMG DYNAMIC PLUS package with front axle locking differential
Completely new for the Mercedes-AMG A 45, the AMG DYNAMIC PLUS package sharpens up the vehicle dynamics even further. It clearly shows the influence of the numerous motor racing successes by Mercedes-AMG on the development of road vehicles.
One major component is the newly developed, mechanical front axle locking differential, which significantly improves traction when driving in a sporty style. The greatest advantages become apparent during fast acceleration out of bends, where the locking differential allows maximum grip and high rates of lateral acceleration. Moreover, the A 45 is stabilised even more effectively during load changes and at high speeds.
The AMG DYNAMIC PLUS package also includes the AMG RIDE CONTROL sport suspension: one of its new features is the two-stage, adaptive damping adjustment. The system operates fully automatically, adapting the damping forces for each wheel according to the driving situation and road conditions. This happens within milliseconds and is infinitely variable, with a wide spread of damping characteristics. This ride comfort and agility are enhanced in equal measure. The driver is also able to preselect the basic damping characteristics in two stages for a personally configured set-up. There is a choice between maximum sportiness or pronounced long-distance comfort at the touch of a button. The RIDE CONTROL sport suspension is also available individually as a separate optional extra.
The speed-sensitive sports power steering fundamentally supports a more sporty driving style with its high steering precision and direct self-steering characteristics. It has two different sets of characteristics: depending on which damper set-up the driver has selected, it provides a taut, sporty or more comfortable steering feedback.
The fifth DYNAMIC SELECT driving mode “Race” is included with the AMG DYNAMIC PLUS package and the AMG RIDE CONTROL sport suspension: this makes the A 45 4MATIC ideally suited to fast laps on the racetrack. The response characteristics of the 2.0-litre turbocharged engine and the accelerator are now even more immediate than in “Sport +”. The exhaust system, suspension and steering remain at “Sport +” level, while 3-stage ESP® changes to “SPORT HANDLING MODE” and allows wider drift angles. The ECO start/stop and sailing functions are inactive. The transmission activates “Race” mode, which is configured to maintain an optimum engine speed in the lowest possible gear when driving at racetrack speeds. “RACE” mode is rounded off by rapid and responsive gearshifts.
Other features in the AMG DYNAMIC PLUS package include the Performance steering wheel with DINAMICA microfibre in the grip area and an AMG emblem on the E-SELECT lever and the main vehicle key.
Shorter ratios: the AMG SPEEDSHIFT DCT 7-speed sport transmission
The agile and dynamic power transfer is assisted by the AMG SPEEDSHIFT DCT 7‑speed sports transmission. Thanks to the now shorter transmission ratios in 3rd to 7th gear, the driver experiences even more dynamic acceleration in all speed ranges. Together with optimised response and shift times, the closer ratio spread ensures better transitions when upshifting.
The control logic for the RACE-START function was also simplified when revising the transmission hardware and software. RACE-START allows maximum acceleration from standstill, and is also a highly emotional acoustic experience. The AMG SPEEDSHIFT DCT 7-speed sports transmission is rounded off with a temporary M mode activated by operating the steering wheel shift paddles in any driving mode, and with the manual transmission mode “M” for individual gearshifts using the shift paddles.
High traction: AMG Performance 4MATIC all-wheel drive as standard
Dynamism, agility and performance – these attributes characterise the standard all-wheel drive of the Mercedes-AMG A 45. AMG Performance 4MATIC combines the best possible traction with outstanding driving pleasure. To suit the dynamic handling requirements, the A 45 4MATIC features infinitely variable torque distribution. The range extends from front-wheel drive only to a 50:50 percent distribution to the front and rear axles. In the compact class this variability suited to the driving situation results in an optimum measure of dynamism, efficiency and traction. A multi-disc clutch with AMG-specific electro-hydraulic control integrated into the rear axle differential almost instantly feeds the engine torque to the rear wheels.
The influencing factors for torque distribution are not only the vehicle speed, the lateral/linear acceleration and the steering angle, but also the difference in rotational speed between the individual wheels, the gear selected and the accelerator position. The all-wheel drive system is also controlled as a function of the selected stage of 3-stage ESP® – from safety-focussed right up to the best possible performance on closed-off racetracks. ESP ® Curve Dynamic Assist is likewise included as standard in the A 45. During dynamic cornering, imperceptible braking intervention on the rear inside wheel creates a defined yawing moment about the vertical axis. The effect: the Mercedes-AMG A 45 enters bends responsively, precisely and always controllably.
New light-alloy wheels in a cross-spoke design on request
The muscular appearance of the A 45 is decisively enhanced by special wheel/tyre combinations. The standard combination is newly styled 10-spoke light-alloy wheels painted in titanium grey with a high-sheen finish together with size 235/40 R 18 tyres.
Four other, attractive light-alloy wheels in size 48.3 cm (19 inches) with 235/35 R 19 tyres are optionally available. As a visual highlight there are new AMG light-alloy wheels in a cross-spoke design, which are available in matt black or titanium grey.
The high-performance braking system ensures fade-resistant deceleration and short braking distances. It has 350 millimetre discs at the front and 330 millimetre discs at the rear, all internally ventilated and perforated to conduct heat away efficiently and prevent fading even in extreme use. The silver-grey brake callipers have white AMG lettering. An even greater visual impact is ensured by optional red-painted callipers with black AMG lettering.
