The motor industry is a competitive business. If one carmaker gets up to something special, be sure its rivals will have something just as tempting out perfectly timed to steal the attention away. Think about it – whenever a big new model comes, its market rivals suddenly get tarted up, facelifted or even just a wheel and stripe job to try salvage some sales against that new metal.

Seems these three were watching each other quite closely too – no sooner than Audi had news of TTS than Mercedes-Benz and Porsche said ‘but look at this!’ in perfect chorus.

And now they’re here - the TTS, Merc’s surprisingly well re-fettled SLK 350 and Porsche’s delightful little Cayman S Sport. But before we compare them, let’s first check out what each these cars mean…

Audi’s TTS is the answer to the dreams of many a fan of the rings who wanted more than just a sexy little runabout in their TT. It was worth the wait – in Audi bringing it up to S spec, it’s addressed most of those supposed performance shortcomings in the quickest TT yet.

TTS is armed with the most powerful version of VW/Audi’s triple Engine of the Year 1984cc turbo petrol direct injection DOHC TFSI four, good for 195kW (that’s a very handy 100kW/litre, by the way) and a consistent 350Nm from 2500 to 5000rpm. Audi claims it’s good for a 5.4 second 0-100km/h with top end limited to 250km/h and a relatively frugal 7.9 litres per 100 km emitting just 180g/km of CO2.

That spins Audi’s hallmark quattro permanent all-wheel drive through a stick-shift six-speed trannie while suspension benefits the standard fitment of Audi’s magnetic ride adaptive damping, which uses varying current applied its magnetized damper fluid to alter its flow characteristics and allow the driver to instantaneously select Standard or Sport suspension modes via a dash-mounted switch.

TTS is built around Audi’s Space Frame hybrid body construction that combines steel at the rear end with the front end hewn from lightweight aluminium.

Aesthetically, like all Audis bearing its S moniker, this TT is set it apart from its siblings by a neat and shiny set of 18-inch wheels, a revised front spoiler, aluminium-look wing mirrors and quad-exhaust tailpipes. Bi-xenon headlamps with LED daytime running lights are new, while TTS’ rear spoiler lifts at 120km/h and drops back down at 80.

Inside, Audi says its comfy and secure heated and height adjustable sports seats and chunky flat-bottomed steering wheel “creates a cockpit moulded around the driver like a sleek-fitting suit.”

Can’t argue there. TTS is also the only car here capable of carrying more than two people – S has the expected TT Coupe split-folding rear seats to allow a modicum of versatility in there.

Audi’s driver information is planted where you can’t miss it in front of you and includes a lap timer function.

The biggest advantage since Mercedes-Benz took the scalpel to its faithful SLK 350 is its highly revised and far freer revving V6 ‘sports’ engine, as Merc likes to call it. Still displacing 3498cc, power is up 24kW to a healthy 224 at 6500rpm while it offers more grunt too - torque is up 10 to 360Nm at 4900rpm.

It seems as if this motor went to AMG for its re-fettle – it’s far stronger throughout the range and even revs through to a lofty 7200rpm. Merc reveals that these improvements are principally courtesy of an increased compression ratio, a new intake manifold and fully revised valve gear.

The Merc now sounds like a sportscar – no more muffled ‘50s English panel van whimper, but the 350 now has a growly and purposeful tone with a neat little Fangio-like heel-and-toe blip on the 7G Tronic’s downshift. That advanced auto ‘box also now boasts steering shift paddles and contributes to much of the car’s improved manner that even makes this Merc fun to drive.

Benz claims the same 5.4-second 0-100 acceleration that the other two here do, while top speed is limited to 250km/h while like the rest of the figures on this car, combined fuel consumption is 10% better at 9.2 litres per100km on the combined cycle with CO2 emissions down 23g/km to 219.

The other aspect that’s made a huge difference to the SLK is the adoption of a new direct-steer system with variable power assistance to ensure ease around town while still providing far better feel, precision and feedback while pressing on.

SLK’s recent re-hash involved 650 new components, some of which were neat little styling tweaks. The front spoiler now boasts an F1 wing-hanger aspect to bring home the company’s McLaren links, while the rear bumper is also new and now includes the obligatory diffuser. There are myriad enhancements to the cockpit too, principally a new instrument cluster and sportier three-spoke steering.

Naturally, when it comes to kit, SLK has it all and then some with more acronyms than we can ever remember trying to describe its vast arsenal of space-age equipment.

So with all these changes clearly aimed at knocking king Cayman off its perceived perch, Porsche had to react. And react it did in fine style.

Clearly Zufferhausen took a leaf out of its immaculate GT3 book in developing this celebratory model. Boasting 223kW, the 3.4-litre Cayman S Sport is 5kW up on its conventional S sibling, while torque is a handy 340Nm over a broad if high 4000-6000rpm band to ensure the sportiest power delivery.

Porsche claims a 5.4 second 0-100 and it seems doesn’t care a hoot for nitpicking EU top speed regulations with a bareback 276km/h top end. Marvellous! It isn’t the most frugal car here though, but not by anything that matters too much at a combined 10.6 l/100km and 256g/km CO2 emissions…

But S Sport comes with a full menu of absolutely necessary equipment and addenda, most significantly its standard Porsche Active Suspension Management and selectable sport suspension while the car sits 10mm lower for ‘an impressive touch of extra performance…’

Aesthetically, its Sport kit brings this Cayman S well and truly alive – its striking GT3-like black rims, exterior mirrors and air intake grids, bi-xenon headlights, bold model designation logos along the bottom of the doors and that twin-chamber tailpipe sports exhaust system (that switches to a more aggressive, louder and more exciting note when the Sport button is pressed) set it apart not only from its lesser-endowed siblings, but also over certain of its somewhat brash rivals on these pages.

Inside it’s special too – trick sports seats come standard, while a most noticeable aspect is the Sports Chrono Package’s clock atop the dash. Sport’s black interior design package is further characterised by an alcantara-finished steering wheel, gear knob and handbrake, while the rim of the circular instruments lacks the usual binnacle on top.

Most importantly, only 700 of these rather special Cayman S Sports will ever be built and each features a special edition plaque on the dash – this one being 007/700. And with only a handful coming to SA, you are ensured of supreme exclusivity over the dime-a-dozen TTSs and SLK 350s that will be cruising William Nichol Drive in the coming months…

So there you have it – three cars that are so different from each other yet so similar in so many ways. The Audi is a turbo-four driving all four wheels, the Merc has a beefy V6 up front turning the rear end and the Porsche is a mid-engined rear-driven sports car. Price wise they’re also nowhere close – the Audi being the bargain at R525 700, the supremely equipped Merc striking the middle ground at R655K and the exclusive Porsche pushing the scale at R795 000. But look at the power and torque and suddenly you can’t throw a blanket over them. The Audi is the least powerful at 200kW with the Merc making 224kW and the Porsche 223, but remember that at Reef altitudes the turbo Audi comes back strong against the others that are wheezing for that thin air, rather than getting it stuffed down its throat. Torque is even closer between 340Nm in the Porsche and 360 for the Merc. Factor their weights in however and the Porsche starts to look quite good on paper… And to really demonstrate how close it is, check out those 0-100km/h figures – they all claim an identical 5.4 seconds. So it’s quite difficult to split them on paper. On the road however, each of these cars has its own particular character.

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