Porsche 718 Cayman GT4 RS review

If you’ve ever wondered what would happen if Porsche stuffed the stupendous 4.0-litre, naturally aspirated, flat six from the latest 911 GT3 into the back of its mid-engine baby-brother, the Cayman… the GT4 RS is your answer. This is Porsche’s GT department letting its hair down, saying ‘hold my Stein!’, and producing the car that we’ve all dreamed about, but never thought they’d have the nerve to put into production.

Yes, it’s the most hardcore, powerful and track-hungry Cayman Porsche has ever made, but with the new 911 GT3 already in existence and a nut-job GT3 RS coming later this year, its remit is a little different. In the words of Andreas Preuninger, head of Porsche’s GT department: “It was high time to have a big party on the 718 platform. This car is a live concert on four wheels, it's such an entertainer and it was such a fun project to make. It’s something that came from our heart and we’ve wanted to do it for a long time.”

Doesn’t it, y’know, step on the GT3’s toes a bit?

We can see why you might think that. At £108,370, the GT4 RS is roughly £15k cheaper than a GT3 with the same gearbox, 20kg lighter, only six seconds slower around the ‘Ring, has an identical 0-62mph time and has the same number of seats with a roll cage behind you (if you tick the no-cost Clubsport package box, which you should). But Preuninger insists they are entirely different beasts: “We are eager to give the GT3 everything we can to let it stay on pole position, like the double wishbone front axle, the rear-wheel steering. On the GT4 RS we didn't look too much into super aero and eking out the last 10th of a second on the track. We tried to find the perfect compromise between road and track driving.”

Numbers, gimmee gimmee gimmee…

We have 493bhp (that’s 79bhp more than the standard GT4, but 10bhp less than a GT3 due to the exhaust needing to take a more tortuous route around the rear suspension), while torque gets a slight bump to 332lb ft and it’s PDK-only - as per the ‘RS’ doctrine. No manual gearbox here. Boo. Still, 0-62mph takes 3.4 seconds (a GT4 with PDK takes 3.9secs) and the top speed is 195mph. Perhaps more impressive is the Nürburgring lap time (on the optional Michelin Pilot Sport Cup 2 R tyres) of 7mins 4.511sec, over 23 seconds quicker than the standard GT4… which is light years around the ‘Ring.

Any other tricks up its sleeve?

Errrr, it’s easily one of the best-sounding cars we’ve ever driven. Ragging a GT4 RS is like having thick treacle poured into your ears… and then an entire wasp colony crammed in after it. It’s just ridiculous. And each journey to 9,000rpm isn’t merely a sound, it’s laced with sucking, vibrations, rattles and spikes of adrenaline. A low-end warble that hardens in the mid-range and becomes silkier until it decomposes into a frantic shudder between 7,000 and 8,000rpm, before a magnificent ear-gasm for the final 1,000rpm that makes your soul sing and your face muscles hurt.

And that’s just when you’re chasing the redline. The rest of the time you’ve got a musical instrument to play with using your right foot on the pedals and fingertips on the paddles. Normally I’d berate anyone who thought deleting the infotainment system (a no-cost option) in the name of saving a few kgs was a good idea, but here it might just make sense. Who needs infotainment when you can summon thunder with the throttle?

And that’s not even the best part. With most fast cars the best noises come from the exhaust pipes - which can sound wonderful from the cabin, but you know it’s sounding even better to whoever you just drove past. You’re effectively providing a public service. But not here, because what you’re listening to is induction noise from the carbon-fibre intakes where the rear quarter windows are normally found. So while it’s a rock concert turned up to eleven for driver and passenger, it’s no more antisocial outside the car than a standard GT4. It’s a trick Singer deployed to great effect on the DLS, but that’s a car that costs about a gazillion pounds more.

Does the world really need a GT4 RS when we already have a more-hardcore-than-ever 911 GT3? Yes. Yes it does; goodness are we happy this car exists. With an all-electric Cayman on the horizon, you can tell Porsche’s GT department senses the combustion engine’s demise and wants to build these types of cars while it still can, these monuments to what’s possible when you mix extraordinary engineering with a bit of fun.

Porsche isn’t limiting numbers of the GT4 RS, just the amount of time it builds them for, so get in there while you still can. Silly quick on track, surprisingly usable on road and a sonic sensation everywhere. Believe the hype… this is likely to go down as one of the all-time greats.