Audi RS Q3 vs. Mercedes GLA 45 AMG: Twice the SUV power in the comparative test
We checked: the term "off-road" does not appear once in the documentation for the 360 bhp Mercedes GLA 45 AMG. Like the Audi RS Q3 with 310 bhp it would rather let off steam on the road and never shies away from the race track.
Why upsize a compact such as the Mercedes A-Class to create an SUV in the first place, to then only lower it again in the sports version? Why incur the cost of developing an off-road chassis, to then reserve it specifically for the top-of-the-range model? And why pretend to be robust by covering it with grey plastic panelling, to then add 20-inch polished alloy wheels?
Mercedes GLA 45 AMG casts all doubt aside in 4.8 seconds
Quite simply: because it's a complete blast. As the fifth Mercedes SUV from the Affalterbach Fitness Studio, the Mercedes GLA 45 AMG continues a rich tradition. Incidentally, in no model is the AMG quota so high as for the bony dinosaur-like climbing frame that is the GLA, of which well over 50 percent have been supplied as AMG models. The Mercedes GLA 45 AMG destroys any remaining doubt concerning is right to exist in 4.8 seconds - with a single sprint to a speed of 100 km/h.
Against its 360 bhp, it is not just the 310 bhp RS variant of the Audi Q3 that is in over its head: even a Porsche Cayman with manual transmission lags 1.1 seconds behind it. When accelerating to 200 km/h, with 18.4 seconds it is even around four seconds slower than the Swabian mid-engine pocket rocket. At around 55,000 Euros, it, like theAudi RS Q3, is however up there with the Porsche when it comes to purchase price. A 2.7-litre six cylinder Cayman can be yours for around 51,000 Euros.
Unlike its scrambling brothers with a G in their name, the all-wheel drive in the Mercedes GLA 45 AMG does not serve to improve the its climbing power. It is more about putting the force of what is currently the world's most powerful inline four-cylinder engine, with a power density of 180 bhp/l on the road. As soon as the front wheels start to spin, a hydraulically controlled multi-disc clutch directs up to 50 percent of the power to the rear axle. Because the hydraulic pump is permanently active, it can react particularly quickly when needed.Hefty 1.8 bar turbo-charging pressure
Therefore even in wet conditions, the Mercedes GLA 45 AMG therefore surges smoothly out of the blocks, revs up nimbly and greats those inside and outside the vehicle with a fanfare of sound from the exhaust valve with each gear shift pause. However, the two-litre bonsai AMG does not even come close to the response performance of a naturally aspirated engine. However, given the record-breaking 1.8 bar turbo-charging pressure, the Twinscroll turbo refrains from the extended intake of air and rolls out an extra-wide torque carpet.
This is all the more gratifying given that the Mercedes GLA 45 AMG can do much more than simply drive in a straight line. It doesn't take much persuasion when cornering, swerving with a sense of determination and pulling neutrally through the corner. On winding country roads it is clearly up there with the quickest and with its smooth yet sensitive steering, it is a lot of fun. If we initially grinned at the thick-walled sports seats with their H-belt design - by the time the track test in Hockenheim came around, we didn't want to go without it, just like the suede-covered steering wheel , the low seating position or the snappy seven-speed dual clutch transmission.
In Manual mode it even holds gear when the four-cylinder engine is already rattling the speed limiter. For the Mercedes GLA 45 AMG, the fast cornering takes place primarily on the Grand Prix course, which it flies through with very little lateral inclination thanks to its low centre of gravity, developing a relationship of trust with the driver on account of its high stability. The driver can feel free to put his foot down early when leaving the corner, without the ESP messing things up for him.
Five-cylinder gurgle in the Audi RS Q3
In the motodrome, the Audi RS Q3 casually counters this with the sound of its five-cylinder engine. With the 1-2-4-5-3 ignition sequence, guttural, gurgling inline turbo engines have been making the hairs on the back of the necks of audi fans stand on end since the 1980s. The 2.5-litre forced induction engine with a maximum pressure of one bar also runs more smoothly over the entire revving range, likewise without increased turbo lag.
It also keeps up better on the straights than the values on paper would suggest - although ultimately it lacks 50 bhp and 30 Newton metres of torque. Accelerating from 0 to 100, the Audi RS Q3 comes in just 0.2 seconds behind the Mercedes. If necessary, the Quattro drive system likewise delegates the traction effort to the rear via a multi-disc clutch. However, hurried cornering does not come naturally to the Audi RS Q3, in spite of the RS logo on the radiator grill and the powerful 255 series tyres, along with 35 series wheels.Audi RS Q3 tackles corners in a more relaxed fashion
Noticeably rocking and pushing over the front wheels, it tries to keep up with the Benz, which weighs two hundredweights lighter. To no avail, also due to the fact that its ESP cannot be completely switched off and refuses to respond to the throttle for much too long when exiting the corner. With a lap time of 2:10.8 mins - measured on the GP course in Hockenheim in a departure from our standard practice - the Audi took precisely three seconds longer than the Mercedes GLA 45 AMG.
The difference becomes particularly clear in the fast sections: shortly before the braking point into the hairpin, the speedometer displays 210 km/h in the Q3, whereas the GLA is at 223 km/h. Because the clear-up work from the DTM season launch is still ongoing in Hockenheim, the short circuit was busy at the time of the test. The otherwise mandatory lap times could therefore not be recorded. However, the cornering speeds in the motodrome do allow for comparisons with other vehicle classes:
in the last test a Porsche Cayman took the southern bend at 106 km/h, the GLA at 145 and Q3 at 99 and 96 km/h. Both of the compact SUVs managed the Sachs bend at 74, whereas the Porsche took it at 80 km/h. Even without the usual lap times, the Mercedes GLA 45 AMG collects more points. Taking the brakes as an example: with its four-piston callipers and 350-millimetre discs at the front, with hot brakes it decelerated from 100 to stationary over a distance of 35.7 metres - one metre fewer than the Audi. And this even though the Audi RS Q3 steps up with eight-piston callipers and hefty 365-millimetre discs.
Audi RS Q3 with better suspension support than the GLA 45 AMG
However, with their hard pressure point, the Q3 brakes deliver the best modulation under heavy load. Their wave-like external contour is said to save half a kilo of weight per wheel. Not everybody should consider the laid back character of the Audi to be a disadvantage. If opting for an SUV, at the end of the day you want to climb in more comfortably and sit up higher. This is exactly the case in the Audi RS Q3, which towers over the AMG by ten centimetres and thus ensures a better view over the busy traffic. Also not a disadvantage: the fact that Audi has maintained a degree of suspension comfort.
Whereas in the event of short transverse grooves the Mercedes GLA 45 AMG and lashes out dryly, and still manages to find uneven patches even on seemingly smooth surfaces, the Sport Q3 skilfully absorbs the bumps on turbulent terrain and surprises with genuine ride comfort. This is all the more surprising seeing as it too showed up for the test with 20-inch wheels and lies 25 millimetres closer to the asphalt than its civilian brothers. On longer journeys Audi passengers can look forward to more space in rows one and two, the more comfortable seats and the much lower noise level. Beyond 160 km/h it gets really loud in the Mercedes GLA 45 AMG. What's more, the larger doors and the wider boot opening facilitate the access and loading of the RS in equal measure.
The fact that the battery in the most powerful Q3 is stored in the boot, for reasons of balance, does, however, mean that precious storage space is used up. Furthermore, its dual clutch transmission does not always respond immediately to manual commands. This shouldn't bother those who generally drive in D. In any case, the Audi is the more practical car for everyday driving.
Date6 February 2015