Archive: 2012 Mercedes-Benz SLS AMG v Oxley Highway

First published in the April 2012 issue of Wheels magazine, Australia's best car mag since 1953.

An epic car deserves an equally sensational road, so Wheels introduces AMG’s SLS Roadster to the best bit of bendy bitumen inland of the NSW mid-north coast.

IT SAYS everything about the SLS AMG Roadster that I’d completely forgotten its value by the time I got it sideways. Sliding half a million bucks’ worth of someone else’s car is no trivial matter. But I was having so much fun that the $500,000 sticker price was the furthest thing from a mind fully occupied with thoughts of speed, balance, grip, steering, throttle, and road.

When you have access to a car as special as this, all you need is the right road to run it on. ‘Car v Road’ will become an occasional feature, not just to keep you abreast of the roads we think are worthy of your attention, but to get to know cars in conditions that challenge them.

With the keys to an SLS AMG Roadster in my pocket and a couple of days to do the most with it out of Sydney, it seemed the Oxley Highway would present the right kind of challenge. The full length of this road, national route 34, runs for 513km, from Port Macquarie on the coast to its western terminus at the Mitchell Highway in Nevertire. But we’re interested in the stretch that any Aussie biker worth his salt will tell you about, the 161km run from Wauchope to Walcha, up and over the hills.

Tonight, the SLS’s job is to get us from Sydney to the Star Hotel in Wauchope. After making photographer Thomas Wielecki’s two-year-old son Enzo cry by revving the SLS to 7000 in the street, I point the SLS’s long, wide bonnet north and hit Highway 1. Enzo’s a bit young for the shocking volume of this Bernd Ramler-designed 6208cc V8. And the popples and backfire explosions from the exhaust, as neat fuel is deliberately injected into it, didn’t help, either. His elder sister Matilda, three, jumped up and down with delight. Sorry Enzo. Soon, mate.

The rain started as we entered the Sydney Harbour Tunnel and didn’t stop for a millisecond for the rest of the test – our constant companions would be the applause of the drops on canvas, and the silent sweep of the stubby wipers. Did it matter? Did it hell. A car with this force of personality is beyond weather, and besides, where we’re going, less grip equates to more fun.

First, the transport leg. For this 375km night run on the Pacific Highway, the SLS just had to be a car, a mode of transportation for two tired heads who’d already spent a full day at work. It performed this menial task well, fairly quiet at cruising speed, its triple-layer lid keeping out even the rowdiest truck roar, the car stable over standing water despite 265/35 Contis up front and 295/30s at the rear. The engine ticks over easily at 2400rpm in seventh at an indicated 120km/h.

We reach the turnoff to Port Macquarie at 10:30pm and dive left. Straight away there are corners, heavily cambered, flowing through a forest, a brief taste of things to come. Then the road opens out and before long we’re admiring the Star pub’s art deco features and scattered furniture, feeling pretty chirpy, gazing from the balcony down at the SLS sitting outside in the steady rain. Several cars drive by and slow, then loop the nearby roundabout and come back for seconds. Four hours’ driving in rotten conditions has confirmed the SLS Roadster as a great grand tourer. But that’s not why we’re here.

Next morning dawns grey and miserable with a constant streaming drizzle filling the air. We couldn’t be happier. Scuttling across from the pub doors, we reload the surprisingly big boot and drop down into the car.

You sit low, the dash and doors high around you, the big wing mirrors at face level, ensconsed in a tiny cabin given the total length. At 4638mm it’s about 100mm shy of a Honda Accord Euro, to pick a random comparison, while its 1938mm width is 100mm more than the Euro. It’s not cramped – you just have no more space than you absolutely need. The seats are firm but comfortable, and multi-adjustable, with fat side bolsters that clamp powerfully into your kidneys. The steering wheel is flat-bottomed, a feature I dislike, but beautifully designed otherwise, its sculpture and ridges locating your hands perfectly at 10-to-two in front of clear silver-backed instruments – the speedo reads to 360km/h. The leathers and plastics and switches and lights and stitching are all top grade – you wouldn’t feel short-changed if you’d just parted with a half a mill for this thing.

Trim materials are soon forgotten – the Oxley demands attention. The road is immediately brilliant as you leave Wauchope. The surface is excellent; dark coarse tarmac with plenty of grip and no potholes or big bumps. It opens out over some long sections, tightens up occasionally into strings of third- and fourth-gear turns, and the SLS is at home, displaying phenomenal grip. It’s early and I’m still going easy. Banking and camber is terrific, especially on a short section 29km in, just east of Long Flat. You can see through the corners a lot of the time, too. Great road already.

Sitting and admiring the SLS’s long profile as I eat a ‘perfect 10’ bacon sandwich at the Long Flat shop, it’s time to leaf through the car’s spec notes. Weight is 1735kg, split 47 percent front, 53 percent rear. The entire engine sits behind the front axle line, while the seven-speed AMG Speedshift dual-clutch gearbox sits at the rear of the car in a transaxle. Power and torque: 420kW at 6800rpm, 650Nm at 4750rpm. Engine weight is 206kg. That’s light for such a big mill.

Looking at the torque curve, a shade under 500Nm is on tap at 2000rpm, with 400Nm available from just 1000rpm. Do we really need turbos? Nah. Redline is 7500rpm. A good indicator of the acceleration on offer is the car’s 0-160km/h time: 7.8 seconds. For me, any car that can run to 100mph (162km/h) in 10sec is shatteringly fast, and to dip beneath that is alien. The Roadster’s standing 400m time is 11.7sec at 199km/h.

Still it rains. And still it doesn’t matter. Nail the throttle and the car squats and grips, the traction control intervening surprisingly little. It’s fast alright, but this road will be more about point than squirt. More open sections follow Long Flat, the Great Divide looms beyond Yarras, then a little yellow sign appears about 60km from Wauchope, announcing corners ‘next 45km’. We stop and take a photo. This is one of Australia’s truly great road signs.

Time to drop the roof. Bugger it, a little water won’t hurt all this carbonfibre and leather, or us. Then we’re off, the car’s bass V8 roar much louder now, bouncing off the trees and roadside banks. The rain gets harder. It doesn’t matter. For the record, water gets spooled from the A-pillar up the side window and across the top lip of the glass, and droplets hit your shoulder constantly, and splatter your face through right-hand bends. This, too, doesn’t matter.

What a road. The surface in the first part of the climb is new and smooth, the excellent drainage and heavy cambering taking care of all standing water. Then the older surface appears and it’s possibly even more fun, with washboard ripples in places and the odd mid-corner bump to keep your mind focused. Only a couple of cut-up fallen trees and the resulting spread of bark and sawdust provide low-grip surprises. Otherwise, it’s all constant and reliable, a roller coaster road.

This car’s good. You’re sitting at the back quarter of the wheelbase, and the front end feels a long way away, but you soon learn that the dynamics are defined by the power of that front end. It is tremendously well stuck down, way up there. You flick the car into a tighter bend – and ‘flick’ is the word, with steering this light and direct – and the front end just grips. Strange feeling, at first, because combined with an almost total lack of bodyroll, you start to feel like you’re driving a big, flat, wide skateboard – like a powerboat crossed with a bathtub, a wide, demented Caterham without the chassis flex. There is no scuttle shake whatever.

The road throws more and more at us and the SLS eats it. Grip levels are other-worldly. For some reason, I expected understeer to set in earlier with the front wheels so far away. Dumb thought. Again and again, I try and fail to make the car plow, and eventually decide to go the other way and have a half-lift off the throttle. And thus we have our slide.

There’s your answer – the heavier rear end unsticks first, the onset of it very evident when your bum is over the rear axle and the momentum’s shifting. As the yaw angle yawns, the stability control clamps down fast, even in ‘Sport’ mode which allows a little more free play. Come on, AMG, you can allow more slip than that. A Corvette is far better in this regard.

Transmission, brakes, steering all get big ticks from me, especially the latter, which is far better than you expect in a Merc. Only delayed downchanges from the DCT spoil things, but I’m tending to change down late anyway given the wet surface. ‘Sport+’ gives you 50-millisecond-faster changes, but alters nothing else. This car lacks the optional adaptive dampers but when you’re pushing on, you don’t miss them.

We don’t stop at Gingers Creek Road House at the top for long, because there’s more of this road to come. What impresses me most, other than the sheer length of the run, is the way the corners are cambered. The road works with you, not against you, and though there are a few tightening radii, none are harsh. All the while, the mist hangs in the trees and the rain pelts down and the big V8 roars and pops, 1758kg feeling like about 1000. My right shoulder is now soaked through and my face covered in rain, but it doesn’t matter. Driving doesn’t get better than this.

Balance is the word. There are few better-balanced front-engined, rear-drive cars. Even a Ferrari GTO doesn’t feel quite as predictable as this thing – it’s a car that has an equally fierce front end, but which relies on electronics to sort out the rear early. The SLS Roadster would be utterly predictable without the ESC safety net on.

The final section of the Wauchope-to-Walcha run is made up of wide-open hill views and long sweepers and straights. Temptation doesn’t get the better of me and I stick to the limit, roof up again now. When we reach Walcha, we follow our plan and turn south onto Thunderbolt’s Way towards Gloucester, but we only get about five clicks before I make an ABS stop, turn around, and go back. The Oxley’s too good to only be done once in a day.

Big-picture view

An excellent way to view this road – or any road – in sweeping 3D glory is via Google Earth. Load the program and ‘fly to’ Wauchope (pictured above). Tick the ‘roads’ box in the ‘layers’ drop-down at bottom left and you’ll see route 34 running west out of town. Drop to about 200m eye altitude and adjust the tilt on the inner top right wheel to look forward, then alter your view direction with the outer wheel and you can point yourself down the road. Then simply drag yourself along it using the cursor. Note the hills and contours. An alternative is to go to the ‘tools’ tab at the top and ‘enter flight sim’, where you can fly down the road in either a fast or slow aircraft. It gets a bit difficult to fly it when you get to the Great Dividing Range, a section of which is shown in the screen shot below. You can also drop into Street View from Google Earth and look at the road and scenery in detail from ground level. In case you were wondering, and you probably were, the ‘45km twisting road’ sign is at 31 24 51.96S, 152 17 14.06E. For a decent overseas adventure, fly to Taxenbacher Fusche in Austria and follow the 107 south. It’s the Grossglockner Pass and very fine indeed.