Sibling rivalry as Porsche’s ‘little brother’ muscles up

The new 718 Cayman GT4 RS is the zenith of the Cayman, finally achieving the same level of driving performance and purity as its older sibling, the iconic 911.

Porsche 718 Cayman GT4 RS blurs the line between road car and racing car. It is powered by the same engine that Porsche uses in its 911 GT3 Cup racing car

If you have an older sibling you’ll know how the Porsche 718 Cayman feels. Or at least how it would feel if cars were capable of human emotions.

But the premise is the important bit, because the 718 has lived in the shadow of the older, bigger, more powerful and, to be blunt, more awesome and iconic 911. Ever since joining the range in 2006, the Cayman has been the “poor man’s Porsche”, due to its smaller size, smaller price and mid-engine layout.

But that’s all changed now, thanks to the new 718 Cayman GT4 RS.

This is the zenith of the Cayman, finally achieving the same level of driving performance and purity as its older sibling. Think of it as Liam Hemsworth winning the family’s first Oscar.

And it’s good timing, too, at least for those who love petrol engines, because Porsche has committed to an electric future for the 718 range.

That may be in the pipeline, but for now there’s this final swansong for the brand’s baby sports car, and it is a masterpiece.

The reason this version of the 718 feels so close to the 911 is simple - it’s full of 911 parts - including the engine and the entire front suspension set-up. From the moment you first get near the GT4 RS, you can see that this is not your average car.

It blurs the line between road car and racing car, with its wild aerodynamic kit, which includes a huge rear wing and an array of NACA ducts and air-intakes spread around the car that suggest there’s a lot going on beneath the surface.

To fully experience the performance potential of the Porsche 718 Cayman GT4 RS you need to be far from public roads

That line blurs further when you learn this 718 Cayman is powered by the same engine that Porsche uses in its 911 GT3 Cup racing car.

It’s the 4.0-litre six-cylinder “boxer” engine that motivates the 911 GT3, making it the most extreme naturally aspirated engine in Porsche’s line-up. It makes a highly respectable 368kW of power and does so at a racing-like 9000rpm, at which point it’s making a mechanical symphony through its stainless-steel exhaust system.

To fully experience the potential of the 718 Cayman GT4 RS you need a racetrack. Porsche tested it around the famous Nürburgring Nordschleife where it cut a lap in just 7:04.51, making it a staggering 23 seconds faster the 718 Cayman GT4 that sits just below it in the range and is, by any standard, a very fast and capable sports car.

It’s not just quick around a track but rapid in a straight line, with Porsche claiming it takes just 3.4 seconds to run 0-100km/h and that it will keep accelerating all the way to 315km/h.

To fully experience the performance potential of the GT4 RS you need to be far from public roads, and while we didn’t get to put that Nürburgring claim to the test, we did hit Sydney Motorsport Park to unleash this beast.

A track session under lights against an array of other supercars, including a Ferrari, McLaren and a fleet of Porsches proved an ideal environment to see what this ultimate Cayman could do.

While it was deeply impressive down the straight, the engine screaming at full revs, it was even more amazing in the corners. This is thanks to the huge amount of changes Porsche has made to enhance the chassis and suspension, including installing the entire front suspension set-up from the 911 GT3 into the 718 GT4 RS.

This is a big deal, because this suspension was developed specifically with the racetrack in mind, leveraging lessons the company has learnt in its decades of competition. It also means the GT4 RS is 30mm lower than the standard 718, with the front and rear tracks extended by 6mm and 8mm, respectively, which helps make it feel more stable when cornering at speed.

And you never have to worry about slowing down either, with the GT4 RS equipped with enormous 408mm cast-iron and aluminium composite front brake discs grabbed by six-piston callipers. These are fed a steady diet of cold air to keep them cool and functioning strongly via the two NACA ducts cut into the bonnet.

Thanks to all these changes, on the track we found ourselves catching cars every lap, even a few previous generation 911 GT3 RS, underlining just how much this “little brother” has grown up. It had no trouble holding its own against the biggest and best names in the sports car business.

And the best part is, despite its extreme on-track personality, it remains a remarkably restrained road car. Sure, it rides a little firmer than your average 718 Cayman and is a bit noisier too, but it still has air-conditioning, a stereo and the other creature comforts you expect.

It’s fitting, too, that Porsche should finally give the Cayman its due at this stage of its journey, because it’s likely to be the final chance we’ll have to compare the 718 and 911 directly for the next decade or so.

Porsche has vowed to keep the 911 petrol powered for as long as it possibly can, leaving its “little brother” to step out of its shadow and become the brand’s first electric sports car.