Popular Mechanics (South Africa)
RIP. SNORTING. FUN.
We get to drive the Mercedes-amg GT family in Germany
After two days of trudging the halls at the Frankfurt Motor Show, it seemed like a good idea to actually get behind the wheel of a car, hit the back roads and blow out a few cobwebs. Let's do this the sensible way, I suggested: start with an entry level model. That way, we acclimatise to driving on the other side of the road.
Now, it's one thing (and quite correct) to refer to the Mercedes-amg GT as an entry level model. It's another thing entirely when you sit down and think about the sheer numbers: 4,0-litre V8 biturbo engine, 350 kw peak power and 630 N.m peak torque. Having choked on that, try these other numbers: top speed 304 km/h and 0-100 km/h in 4,0 seconds.
Not that you'd have any success getting much beyond 200, never mind 300, on the cluttered autobahn that we briefly jumped on to a few minutes later. Ditto the easy-on-the-eye countryside, criss- crossed by uncomfortably narrow B-roads, on the drive from Paderborn – where Nixdorf computers once reigned – to where the GT'S big brother R waited at the Bilster Berg track an hour's drive away.
But there are several more strings to the GT bow. The successor to the gullwing-door SLS that was the first in-house production from Merc's AMG performance arm now encompasses a total of eight models. That range includes four coupés and two roadsters plus two customer sport racing cars, the GT3 and GT4.
My co-pilot and I got handson with the coupé, the roadster and the golden anniversary GTC Edition 50, as well (of course) as the R, current fastest production road sports car around the Nurburgring at 7 minutes 11 seconds. Apart from the engine outputs, rang-
ing from 350 to 430 kw, there are also various versions of engine mapping, suspension and aerodynamics available. But there is a technical strength that all have in common, says AMG product manager Axel Wollesen: • Front mid-engine concept with dual clutch transaxle at the rear • Racing suspension with aluminium double wishbone • Active optimisation of aerodynamics • Intelligent lightweight design • Highly dynamic driving experience • 231 kg aluminium spaceframe body.
It's safe to say that no matter what version of the frontmid-engined GT you pick, you
are pretty much guaranteed a memorable drive. Common to all of them is a ride that's firm without being harsh and a soundtrack that just screams out for the Loud button. (I'll apologise publicly here for having flipped the switch that turns the exhaust note from a menacing rumble to a thundering drumbeat that made the residents of Lichtenau's eyes pop and got us the thumbs-up from at least one little boy.) The thing is, the sights and sounds and feel of the GT make you always aware that this is very much a sports car, without making it hell on wheels after a few minutes. That's even true of the roadster, top down or up. It took a while, in fact, before I realised that the open-topped model felt every bit as stiff over bumps and in cornering as its
coupé sibling. There wasn't even the typical extravagant shimmy through the steering wheel to indicate the inherent compromise you'd expect in body rigidity. Score one for the rigidity inherent to Merc's oft- touted aluminium-rich Intelligent Lightweight Design.
The old-school front-engine rear-drive layout means that the view out the front involves a lot of bonnet. Some drivers prefer to be perched more over the front wheels, as with midor rear-mounted engines. I'm a little torn: there's something deeply satisfying about a car that makes no concessions about being a big, powerful grand tourer, finish and klaar. Yet, as it danced nimbly from switchback to switchback out on the roads, or flicked through some testing leftrights on the track, there's no question of this car's agility.
On the track, a first outing on a surface still damp after rain meant taking things even more cautiously than I would normally have on a completely unknown circuit. Even so, getting too enthusiastically on the accelerator to exit the sharp right-hander on top of the pit straight resulted in a heartstopping tail-out slide that called on the best efforts of traction control, the GT R's rear- wheel-steering and my reflexes.
By afternoon, though, things had dried out. That's when the R's fantastic balance of power, agility and grip came into its own. It's a blend that rewards skilled drivers by rising to the occasion, responding to wellschooled inputs and, when necessary, dipping into clearly deep reserves to provide ondemand massive thrust and neck-straining braking, time and again. It just never felt like you needed to back off, to let things calm down. As if it was meant for this scenario.
I could see that this was exactly how things were playing out up ahead, as the two cars leading our three- car train dived into corners, sizzled through them and rocketed away from me into a lead, only to have to trundle a few hillcrests away to allow me to catch up. No excuses, but just for the record, my skill levels are not quite up to those of our lead driver, multiple DTM champion Bernd Schneider…
even within the same model year.
Don't worry, though. Porsche didn't go full crazy with the building a drivable smartphone idea. Stuttgart reached out to Cupertino when it wanted to cosy up to a smartphone maker and the iphone integration runs quite deep. The Oneconnect application, for example, uses Touchid for authentication and makes use of 3D Touch shortcuts. There's also an Apple Watch complication and the engineers did let slip that Touchid could be used for keyless entry in the future.
Porsche's user interface is elegant and seems easy enough to master, but the larger question is whether it is in the best interests of the manufacturer to spend all that time and effort of setting up servers and developing software when most customers will simply plug in their iphone and use Apple's solution. Google's Assistant and related services are already an essential part of the modern technological experience, the same with Siri and the related IOS software solutions. These are mature ecosystems built on a foundation of at least a decade of research and development. So let's rather focus on the things the new Cayenne really excels at.
SOMETHING OLD Gone is the double wishbone front suspension and, in its place, a new multilink system built with an aluminium sub-frame. Porsche's engineers have simultaneously shed 65 kg of weight and dramatically improved the driving dynamics while also removing vibration from wheel imbalances. Around back is the vintage multilink set-up, but now forged aluminium links alongside lighter steel links. Rear- wheel steering was the key factor behind the shift to this new configuration.
Well that and the off-the-shelf design Porsche received through its involvement in the larger Volkswagen group. The new chassis design is almost identical to that of Audi's reimagined Q7. Granted, that was an evolution of Porsche's own 918 rear axle. Rear axle steering in this instance, however, is used to help make the SUV more drivable in lower speed
situations. The system works only up to about 80 km/h and reduces the turning circle to 11,5 m from the original 12,1 m. The craziest thing, though, is that this wheel movement is achieved through the flex of the rubber bushings on input from electromechanical actuators, as there is no actual steering rack.
SOMETHING NEW To complement the rear-wheel bias in power delivery (front wheels are powered on-demand), the new Cayenne now comes with mixed tyres. The rubber on the larger new wheels comes in 255/55 and 275/50 for the 19-inch and 285/40 and 315/35 for the 21-inch option. This shift is inspired by Porsche's experience with sports cars and is said to increase comfort as well.
On stopping duty, however, is a worldfirst Porsche Surface Coated Brake (PSCB). At its core the new brake disc is still cast iron, but now with a heat-applied tungsten-carbide coating. The new coating is significantly harder than cast iron and offers 30 per cent longer service life. It's mated to specifically developed pads and the combination is said to also significantly reduce brake dust. You can still specify Porsche's acclaimed ceramic composite brakes, but this new development offers comparable improvements to stopping at a cheaper price point.
SOMETHING BORROWED Dipping into the Q7 parts bin also gains the Cayenne the benefit of excellent electromechanical roll stabilisation. The threestage planetary gearbox at the heart of the system is driven by an electric motor powered by the 48 V system, allowing for anti-roll bar torsional rigidity adjustments within milliseconds. This design effectively splits the anti-roll bar in two, joined by a pivot motor which will spin the two in opposite directions depending on roll angle. Decoupling the anti-roll bar is then just a matter of allowing the mechanism to freewheel.
SOMETHING BLUE Weight savings in the body construction were achieved through using more aluminium than ever before alongside boron-alloyed steel. Aluminium use is actually up to 47 per cent, with even greater use forecast should safer cars bring about changes to legislation around body structure. Up to 135 kg was shed in total over the previous generation. Increased use of aluminium also means new production methods, one of which is the sixstage press method to produce the side panel from a single sheet of metal. There is only one manufacturer in the world that could accommodate this request.
In all, Porsche has achieved something quite special with its new Cayenne, a true SUV that is as capable on the road as it is off it. Whether it's enough to compete with Range Rover's new Velar and similar SUV offerings reaching our market in 2018 remains to be seen. The only certainty is the Stuttgart-based company's commitment to engineering some of the finest motorcars on the planet.