Bahn finds

Audi lobs a 331kW grenade into the ubercoupe sector in the chiselled form of its latest RS5. Should BMW and Mercedes-AMG be worried?

WORDS ANDY ENRIGHT PHOTOS THOMAS WIELECKI

AUDI RS 5 | BMW M4 PURE | MERCEDES - AMG C63 S

On a gnarly cross-country route, the others wouldn't see which whay the RS5 had gone

representing a durable class benchmark. The Pure trim is an Australia-only model that strips out big-ticket items like adaptive LED lights, leather and premium audio system. Mechanically, it only differs from the M4 Competition by switching from 20- to 19-inch alloys. The Pure shares the Competitionís 331kW/550Nm 3.0-litre twin-turbo six and has an identical suspension tune, though our test car featured the 20s optioned back in (for $2500 more). With a $139,000 base price, the M4 Pure is comfortably the most affordable car here.

The AMG has clearly been on the juice, now sporting muscular wheelarch bulges, fat rubber and an aggression thatís entirely absent from its comparatively snake-hipped C43 sibling. The pugnacious stance works well, this remedial work fixing the standard coupeís rather apologetic rear end. The only V8 of the trio, the 375kW/700Nm 4.0-litre Merc fronts up with the most grunt and the heftiest sticker price of $163,612. Add $9900 to that to get the car as tested here, complete with AMG ceramic front stoppers.

Slotting neatly between these two bookends comes the 331kW/600Nm 2.9-litre V6 Audi RS5 which has been sensibly pitched at $156,600. The eye-catching Sonoma green paintwork, an extended carbon package (including the roof and engine cover) and a Technik package, which includes colour head-up display, Matrix LED lights and a Qi wireless charger, bumps that up to $179,346 as-tested.

On the straight and narrow

@wheelsaustralia 63 One issue that arose several times during the course of this test was the mystery of the Audiís recurring lane keep assist.

Halfway through a drive route, and without consciously switching it on, the Audi would tug at the steering, having switched into this mode. It was later revealed that the LKAS engagement button, located on a wedge at the end of the indicator stalk, is very easy to depress when casually flicking the wand down for a left turn.

Thereís real bite and character to the M4. Itís the only one you could grow to love

FIRING UP more than 1000kW of aggro at 6am is going to make you unpopular, even in a town as octane-addled as Bathurst. The Mercís bent-eight emits exactly the correct frequency to turn motel windows into giant drum skins, bleary-eyed curtain twitchers unable to figure out at which miscreant to direct their stink eye.

Itís a fat, meaty wub-wub with an old-school appeal that sounds anything but turbo-neutered. The M4 is the midrange, with the RS5 adding some tinnitus treble to really round out the sonic barrage.

Received wisdom has it that the C63 S is going to be cast as the hooligan here, the point-and-squirt hot rod thatís long on drama but light on subtlety. It plays up to that casting, initially at any rate, with a wilful determination to bend the coding of its traction control software to breaking point and inflicting a ride quality around town thatís marginally better than setting off down the Dipper after zipping yourself into a hard-shell Samsonite roller. Race mode has your foot bouncing on the throttle pedal like a Tullamarine taxi driver with St Vitusís dance.

By contrast, the M4 feels as if Munich has commissioned Tempur for the damper tune. By most normal measures itís still firm, but there is a degree of suppleness thatís missing from the Benz. The bandwidth between the M4ís Comfort and Sport+ settings isnít huge, certainly less than the C63ís arc between acceptable and vertebra-clacking, while the Audi effectively has two damper settings. Comfort is where youíll stay almost all the time, giving the RS5 a genuinely plush GT car ride, with Sport being reserved for smoothly surfaced twisties. On typically scabby country roads the latter will have your head coming into contact with the roof lining a little too often for comfort. Kiss goodbye to your sunnies if you occasionally prop them atop your noggin.

Snapper Wielecki has identified a suitably scenic corner for us to play on (33į33í18.22ĒS, 150į 8í36.31ĒE, if youíre interested), which requires a fair degree of commitment to make the cars look lively for his Canon.

Itís here that the Mercedes shines, with just enough reassuring bodyroll and a beautiful, buttery transition into power oversteer. Even with the ESC switched on, you can feel the electronic limited-slip diff smearing in and out, allowing just a spritz of rear end movement.

In ESP Sport, itís a whole lot more lenient, responding well to a gentle roll of the wrists. The weight of the engine makes itself felt if youíre lazy with your braking or ambitious with corner entry speeds but greater negative camber, stiffer bushings and a model-specific rear-axle carrier combine to give the C63 S a sweetly textural, benign feel at the limits of grip, belying its somewhat one-dimensional image.

Rolling from throttle to brake reveals a slightly clunky pedal positioning, Mercedes Ė like many manufacturers Ė retaining a higher brake pedal than accelerator; a legacy of manual car heel-and-toe requirements. Out of the corner, the Mercedes feels the strongest, with a comical slab of torque arriving at 3000rpm and persisting with no let up to 5000rpm.

The AMG-Speedshift 7 lets you hold a gear if the requisite button is engaged, but despite its surfeit of cubic centimetres, the AMG engine operates best in that 2000rpm band and the gearbox software has a better feel for this than you or I. The optional ceramic front stoppers help shrug off the carís 1725kg heft and, unusually for carbon picks, are easy to modulate, representing a key point of difference between Affalterbach and Munich.

The M4ís four-piston front brakes are the weakest aspect of its dynamic palette. Itís a perennial M-car complaint but BMW doesnít seem to be listening, deeming them sufficient for fast road driving. Thatís also open to question, the pedal going long after a

Buttoned Down Key driving functions should always be within easy reach and both BMW and Mercedes- AMG feature an array of buttons to instantly tailor suspension, steering, transmission and stability control settings. In the Audi, many of those crucial functions are relegated to the MMI screen. The M4 goes one stage better than the AMG by ensuring all of these controls are located on the driverís side of the gear selector.

Belt and Braces

Both the RS5 and the C63 S are fitted with Ďbelt butlersí, the robotic arm that feeds you your seatbelt. The M4 isnít and its long doors mean that itís quite a stretch to reach over your shoulder for the buckle. The BMW also delivers quite a squeeze when the seatbelts are engaged, tensioning them firmly. This feature seems to be universally hated by most passengers Iíve carried in modern BMWs, with females finding the tensionerís hug particularly unwelcome.

If we totted up scores, the RS5 would undoubtedly emerge with the biggest number

few committed applications on a downhill stretch. The M4 also suffers from oversteer. Perhaps that needs qualification. Unexpected oversteer has given more than a few drivers a case of the frights and much of that may well be caused by the Active Sound symposer.

Between 2500 and 3000rpm, the sound piped into the cabin is a muted, deep rumble. It doesnít sound particularly potent, yet at this point in the rev range, the engineís making its full slug of 550Nm; more than enough to light up the rears. BMW claims the symposer makes up 2-3 percent of the sound with the rest natural, but the careful wording of its claim is disingenuous.

Listen to a car with the symposer disabled and itís markedly different. This is whatís spooked so many, the weird disconnect between whatís happening at their ears and what the rear contact patches are having to contend with. In short, oversteer arrives before you expect it and itís spikier than the AMG, the BMWís Michelin Pilot Super Sport rubber being less forgiving than the more malleable ContiSportContact 5P boots on the Benz, which exhibit a more manageably ramped transition from grip to slip. The M4 also has the loosest body control of the trio and requires a little more consideration when flicking from corner to corner.

Get into the RS5 after a committed blat in either of the other two and it feels as if youíre wearing noisecancelling headphones. The Porsche-developed V6 (youíll find similar ironmongery under the bonnet of the Panamera 4S) sounds a little too mannered, even when given a merciless prodding. I found myself clicking my jaw because I thought the altitude drop on the road had caused my ears to need popping. No, itís just a lot quieter. Quieter and quicker. The numbers against the stopwatch tell a compelling story and thereís little doubt that on a gnarly cross-country route, the other two wouldnít see where the RS5 had gone. It gives so much and asks for so little in return, which is both its greatest talent and most significant shortcoming.

The steering, even in Dynamic mode, is a bottle of

Pure Blonde to the AMG and M4ís steins of Warsteiner.

The front end of the RS5 is predictably mighty, with huge grip aided by the widest tyres of the trio, 275/30ZR20 ContiSportContact 6s. Try to get the car to misbehave and it all gets a bit reluctant, the 40:60 rear bias seeming to promise a level of throttle adjustability that the Audi isnít keen on indulging. Itís undeniably effective at demolishing a string of corners, the new five-link rear end replacing the trapezoidal-link arrangement that underpinned the old car. It should be noted that Aussie cars feature the quattro rear sport differential Ė an option on Euro models Ė which delivers a greater percentage of fun to the outside rear wheel.

The V6 is freakish in its sheer relentlessness, with instant go from 2500rpm right through to the redline.

Thereís next to no let-up. The only automatic gearbox of the trio makes a solid partner, slurring up and down ratios almost imperceptibly, holding gears to the limiter if you prod the lever to the left and being way slicker in its operation than the stalk-mounted Benz shifter or the maddeningly over-complex BMW contrivance. Audi scores a minus point for getting the shift action the wrong way round though. And on an RS model too. Tut.

The RS5 delivers the most refined cabin of the trio at cruising speeds, although loose chip surfaces set up some extravagant tyre rumble. The Mercedes is all exhaust boom, with or without the extra noise button engaged, while the BMW is largely civilised below 4000rpm, whereupon it all starts getting a bit exciting. While the Audi boosts its GT credentials with impressive driveline civility, it scores a few surprising ergonomic demerits.

The cabin is undeniably gorgeous, with hexagon

Received wisdom has it that the C63 S is going to be cast as the hooligan here

Light is right

Fuel usage on our test route corresponded fairly closely to the kerb weight of each of our vehicles. The lightweight (1580kg) M4 CS was the most parsimonious at 12.9L/100km, despite probably being driven the hardest. Next up at 13.0L/100km was the 1585kg M4 Pure, followed at 13.9L/100km by the 1655kg Audi RS5. The portly eight-pot AMG hefted 1725kg to a 14.8L/100km result, this figure made a little more palatable by the biggest fuel tank of the bunch.

shape, Walter de Silvaís finest moment, but itís a confident and assured piece of vehicular sculpture. The AMGís glitzy shtick will, for many, justify its elevated price tag. Great seats and showy alloys aside, the M4 looks slightly dull.

This alone ought to be enough to guarantee the RS5ís success, from a sales perspective at least.

We donít count registrations as the fairest way of keeping score. We never have and never will, so itís time to crown a winner of these three cars. The M4 is undoubtedly the most flawed of the trio, yet itís a car that rewards an extended period of acclimatisation. Whatís more, thereís real bite and character to it. Yes, itís finishing this test third, but of the three, itís the only one I reckon youíd grow to love, and itís the only one thatís also offered with three pedals. The Pure model probably ought to be a simpler, rawer thing, and that car doesnít exist as yet. The M4 CS (see sidebar, below) shows what can be done but, to put it bluntly, its price is a joke. Model by model, BMW continues to just miss with the M4, like a sniper repeatedly overcompensating the adjustment on a scope.

The RS5 is an interesting one. It excels on so many objective counts that were we totting up scores, itíd undoubtedly emerge with the biggest number. Itís the newest, slickest, most economical, and quickest on a challenging road, but it never connects with the driver on any significant emotional plane. Itís more Ďgood Audií than bad, but it emerges as a bit of a curateís egg: itís a melange of overpolish in some areas and somewhat underdone in others. Its optimum ride/handling setting is, frustratingly, somewhere smack between the binary Comfort and Dynamic modes and that engine needs more attitude and flintiness to it.

Which leaves the Mercedes-AMG as last man standing as the other two manage to count themselves out. Yes, the ride could be better and the shouty design will dissuade some but, unlike both of the others, this is a car that doesnít seem to take itself too seriously. This impishness is infectious and encourages you to have a little fun. Itís less one-dimensional than you expect which, admittedly, is not saying much, but it nails a brief that AMG seems to understand better than the others. Itís about an experience removed from the ordinary and the C63 S drenches you in just that from the first prod of the starter button. Notch another one up for Affalterbach.

BMW M4 CS

The C63 S is a car that doesnít seem to take itself too seriously