Rocketing down the highway

Auto & Audio April 23, 2014 00:00

By Kingsley Wijayasinha
The Nat

4,226 Viewed

In "C" mode, Mercedes-Benz's A 45 AMG is a tame - and economical - beast, but trigger the "Sport" or "Race" mode and the brilliant engine will give you an adrenalin-pumping time you'll never forget

It’s been ages since I’ve driven an AMG model from Mercedes-Benz, so when the opportunity to drive the diminutive A 45 AMG came up, I was nothing but excited. 
As the official tuning division of the German luxury carmaker, AMG had in the past concentrated on larger models, fitting them with beefed-up V8s and V12s that turned the elegant Mercs into fire-breathing dragons. The A 45, however, doesn’t feature a large engine like its elders. There’s no characteristic 4.5-litre V8 engine – as some would guess from its name – but a turbocharged 2.0-litre motor. Yet, don’t let this fool you. 
With 360hp and 450Nm at its disposal, this is the most powerful 4-cylinder turbo engine in series production in the world (producing as much as 181hp per litre). 
I’m starting off describing the engine because it is undoubtedly the strongest highlight of this car. Mated to a 7-speed dual clutch transmission, the twin-scroll turbocharged direct-injection engine performs brilliantly, catapulting the car from stationary to 100km/h in 4.6 seconds and to an electronically limited top speed of 250km/h. 
Strangely enough, the A 45 doesn’t have a smart entry system or push-start button, so you fire the engine the conventional way with a key. But what you hear is a nice welcome growl from the super sporty exhaust system. 
As always, I drove out of Mercedes-Benz’s headquarters on Sathorn Road and headed for the expressway entrance nearby, paid the toll fee, accelerated up the ramp – and was a little disappointed. Problem was that the car was running in the default “C” mode (Controlled Efficiency), which helps improve fuel economy but takes much out of the driving fun you deserve from this pocket rocket. Throttle response was slow and you could feel the turbo lagging at low revs. Hell yes, I needed to get up to 4,000rpm before any serious acceleration could take place. 
So to properly drive the A 45, what you need to do is press the “S” mode (Sport) – and all hell breaks loose! The engine roars louder, and during full acceleration, each upshift is accompanied by an adrenalin-pumping engine backfiring note, although I have no idea whether flames actually are blown out of those rectangular tail pipes. What the ECU does here is briefly and precisely interrupt ignition and injection under a full load, resulting in quicker gearshifts as a fusillade of tail-pipe bursts produces wonderful sound effects. 
Shifting time is as quick as in the SLS AMG, although there are some idiosyncracies, such as very slight jerks on crawling speeds. And despite the sporty nature of the car, high-rev downshifts aren’t allowed, meaning that in some second gear corners you may have to go around it in third, or lower the vehicle speed altogether. This has become kind of symbolic with Mercedes cars – BMWs and the M cars are more eager to downshift in this case. Nevertheless there are a good number of electronic programmes to play with, including launch control and the 3-stage ESP (Electronic Stability Programme), which offers “ESP On”, “Sport Handling Mode” and “ESP Off”. 
Mercedes claims fuel economy figures that are impressive, such as 16.9 to 17.2km/litre on the highway. But bear in mind that this is during cruising and whenever you start to accelerate, the figures fall dramatically according to the power unleashed. No kidding, it can easily drop to 5km/litre during sporty driving. 
But trust me, it’s hard not to floor the A 45’s throttle whenever traffic conditions allow. The A 45 comes with a variable all-wheel-drive system as it would be hard to gun all the 360 horses through only the front wheels. The A45 normally drives like a front-wheel-drive car, but if the front wheels start to slip, as much as 50 per cent of the torque can be sent to the rear wheels. 
Another thing I like about the A 45 is the steering. It’s refined, precise and has the right weight, while the wheel itself is also great to grasp thanks to its right size and shape, featuring a flat bottom section. Equally impressive are the brakes. Huge ventilated and cross-drilled discs both front and rear generate spontaneous and massive stopping power at high speeds. The suspension of the A-Class has been dramatically improved with the AMG sports suspension with tuned springs and dampers plus larger stabilisers. Good-looking black 19-inch AMG wheels are offered along with 235/35 tyres both front and rear. 
While the normal A 250 AMG’s suspension feels harsh and too sporty for day-to-day driving, the A 45’s suspension doesn’t multiply on that. I drove it for three days and had nothing to complain about the ride quality. But you’ve got to be a little careful when parking or crossing speed bumps as the front spoiler can get damaged. 
The test car I borrowed from Mercedes-Benz Thailand came with stickers all over that made it look like a racing car. But without them the A 45 is a little more discreet with the “Edition 1” styling. There are several differences with the standard version, such as the twin-blade front grille, front spoiler with those tiny black air splitters, side skirts, rear diffusor and the rear spoiler. 
The interior also has differences, such as the carbon-fibre trim and the red air vent dials, sports seats, sports steering and four red seatbelts (the fifth is black). The speedo reads up to 320km/h and there’s a “Race” menu that allows the driver to record lap times during circuit driving. Meanwhile, when in “M” (manual) mode, there is also a shift light indicator reminding you to change gears. 
Of course, you get all the equipment expected from a Mercedes-Benz including auto bi-Xenon headlights, high beam assist, navigation, Bluetooth, Internet, etc. In fact, it’s fully loaded and the only bad news seems to be the retail price. The A 45 AMG costs Bt5.79 million, which is more than two A 250s combined. 
Mercedes-Benz says the car is targeted at customers aged 30-45, which I think is due to the price, not the size of the car that is more suitable for a much younger crowd. Nevertheless, if you’re not concerned how people look at you when you get out of the car (if you’re older than 40 like me), the A 45 AMG can serve as a substitute for a much more expensive sports car. It offers tonnes of driving enjoyment and performance, while maintaining a high level of functionality offered by a subcompact hatchback along with respectable Mercedes quality. 
As for me, there’s just one question left: How would it fare against the BMW M135i, another German hot hatch with 320hp and 450Nm plus all-wheel-drive? Now pitting these two cars against each other on a circuit would indeed be awesome. 
Mercedes-Benz A 45 AMG 
Engine: 4-cylinder DOHC 16-valve turbo 
Displacement: 1,991cc 
Bore and stroke: 83x92mm 
Compression ratio: 8.6:1 
Max power: 360hp/6,000rpm 
Max torque: 450Nm/2,250-5,000rpm 
Transmission: 7-speed DCT (Dual Clutch Transmission) 
Ratios: 3.86/2.43/2.87/1.05/0.78/1.05/0.84 
0-100km/h: 4.6 secs 
Top speed: 250km/h (electronically limited) 
Fuel economy (km/litre): 
11-11.4 (city) 
16.9-17.2 (highway) 
14.1-14.5 (combined) 
CO2 emissions: 161g/km 
Suspension (f/r): McPherson strut, stabiliser/multi-link, stabiliser 
Steering: Electro-mechanical powered rack-and-pinion 
Turning circle: 11.0 metres 
Brakes (f/r): vented and cross-drilled discs all round with ABS, BA and 3-stage ESP 
Dimensions (mm): 
Length: 4,359 
Width: 1,780 
Height: 1,417 
Wheelbase: 2,699 
Track (f/r): 1,557/1,561 
Weight: 1,555kg 
Wheels: 19-inch alloys 
Tyres: 235/35 R19 
Fuel tank capacity: 64 litres 
Price: Bt5.79 million 
Distributor: Mercedes-Benz Thailand