AUDI TT RS
Audi rediscovers 5-cylinder turbocharged power for its new 335bhp sportscar
Even as I opened my big mouth to ask quattro GmbH’s technical director whether the new Audi TT RS comes packaged with a five-cylinder turbo simply as a marketing ruse cooked-up to reconnect the brand with the glory days of the old Sport Quattros, I reckoned I might be in for a black eye.
‘Do you see any marketing men here?’ he demanded. ‘No you don’t, because at quattro we are all engineers, and what you have come here to see is not marketing, but an engineering project, one hundred percent.’ Well, I might have guessed he would say something along those lines, but the question hadn’t seemed too daft considering the emphasis placed on the historical connection between the classic Sport Quattros and the new TT RS in the brief presentation we’d just sat through.
The TT RS’s new 2.5-litre engine started life in the less than glamorous surroundings of the US-market VW Jetta’s engine bay, but has undergone a thorough re-work at the hands of quattro GmbH. Boasting an output of 335bhp – or 137bhp/litre – the engine is remarkably compact, with a gap between the cylinders of just 8mm helping to keep overall length to 494mm. Bore and stroke are 82.5mm x 92.8mm and the firing order is set at 1-2-4-5-3, alternating between adjacent cylinders and those further apart, which Audi says is responsible for engine’s distinctive rhythm and sound.
FSI direct fuel injection injects fuel into the combustion chambers at 120bar, with a swirling motion helping to cool the cylinder walls and thus reducing the risk of knock during combustion. FSI also allows a high compression ratio of 10.0:1 which contributes to the engine’s efficiency.
The turbocharger is sizable too, theoretically able to compress 335 litres of air per second, and with relative boost pressure of up to 1.2bar. The turbo casing has its own oil supply and a cooling system supplied by its own water pump. If you don’t want to use all the power generated by this advanced new unit, Audi also claims a remarkable 30.7mpg is achievable on the combined cycle, as are the lowest C02 emissions in class at 214g/km. How nice!
Not a bad showing on the technical front then, but how does the TT RS stack up where it matters? On the road, and also in this case on the famous Belgian F1 circuit at Zolder, around which Audi had kindly invited PistonHeads to try their new sports machine on the generous presumption that we’d manage not to embarrass ourselves at the model's aptly-titled 'dynamic launch' for media. (In the end, having fallen at the first hurdle by ‘going round again’ when plied with an unexpectedly fine lunch of lobster and steak béarnaise, I reasoned that writing-off a shiny new TT RS on a damp track where former Audi Le Mans driver Michele Alboreto won a Grand Prix for Ferrari would not be conducive to future invitations. So you may be disappointed if you read on hoping for a detailed critique of the TT RS's handling 'beyond the limit'.)
Since first sampling the RS magic in an RS 2 Avant in the mid-1990s (and scaring myself witless, as I recall), the badge has generally implied to me a sort of manic over-achievement on Audi’s part, usually through a ballsy engineering-led effort to convert (relative) mediocrity to hilariously inappropriate and unexpected performance.
On paper, the TT RS delivers the goods without question, its combination of light weight (1450kgs) and high output delivering fearsome accelerative force. Audi quotes a 0-62mph time of 4.6secs, and a top speed of 174mph when the 155mph limiter is deactivated, and there is certainly no lack of performance out on the road. Driving the Coupe the couple of hundred kilometres on the test route from Cologne airport to the track left no doubt as to the commanding power available, or the ability of the quattro chassis to transfer it safely to the tarmac.
If you specify Audi’s optional magnetic ride adaptive damping, the Sport button also reduces oil flow in the dampers to keep the car even flatter in hard cornering. That said, the standard chassis set-up that I tried seems to perform ably with little body-roll to unsettle fast progress, combined with a ride quality that is generally well resolved given the indisputably high level of cornering ability on tap. Driving on UK roads may amplify a sense that the damping could offer a little more subtlety at times, but hopefully we’ll get a chance to find that out in due course.
It struck me en route to Zolder that perhaps the TT is simply too good a starting point for the 'classic' RS treatment. Whereas other RS models get radical chassis mods with extra anti-roll bars and bespoke componentry, the hottest TT makes do with a set of mildly uprated springs and dampers, revised suspension bushings and tweaks to the level of electric steering assist. Brakes are upgraded too, with 370mm front and 310mm rear ventilated discs gripped by four pot callipers that felt reassuringly effective on the road.
Of course on a damp-ish track, even with the ESP left resolutely on (see excuse proffered above), there is definitely an amount of fun to be wrung out of the TT RS. The car’s traction when powering out of corners is notably good, while the excellent power to weight ratio, slick gearchange and smooth delivery of power from the turbocharged engine all conspire to encourage a maximum attack approach – particularly as the quattro’s tendency to gentle understeer in extremis confers a reassuring sense of security that things are never likely to go too far wrong. The downside is a corresponding lack of engagement with the chassis, as even when lapping as fast as you might care to the car responds benignly with none of those moments of 'adjustability' that make the hairs stand up on the back of your neck when enthusiasm overwhelms ability.
However, in spite of its cracking new engine and the big numbers, some may feel the latest TT delivers its performance in a manner that’s just a little too unadventurous. I don't think I'm alone in wanting an RS to make me feel like a naughty schoolboy every time I gun it up the road, yet this is a car that seems to be aimed squarely at the grown-ups.
Without the RS badges, I think I'd have flown home thinking the fastest TT was quite a machine, combining mighty performance, exemplary composure and a general sense of all being right in the world of Audi. With the RS badges stuck on it, I'd like just a little more insanity please!