Up next:

Porsche 718 Cayman GT4 - the naturally aspirated flat six Cayman is here

Published: 17 June 2019

► New 2019 Porsche 718 Cayman GT4
► Pure-bred 414bhp flat six thrills are here
► Tin-top sibling to new 718 Spyder

Here’s the Cayman for purists - the new 2019 Porsche 718 Cayman GT4. It’s a direct replacement for the first hardcore Cayman to come out of Porsche Motorsport: 2015’s GT4. The new 718 Cayman GT4 follows on from that, the 911 R and the option of a manual ‘box on the 911 GT3.

This time there’s a soft-top GT4, too - and we deal with the 718 Spyder in our separate story here.

To get straight to the point and put an end to internet rumours, the engine powering both of them is a 4.0-litre naturally aspirated flat-six with 414bhp.

Is that 4.0-litre flat-six a real Porsche 911 GT3 motor?

It’s not. Costs prohibit it, as Porsche GT boss Andreas Preuninger reckons the GT3/GT3 RS 4.0-litre flat-six is about the most expensive series production engine in the world – and that’s before you go through the re-engineering process to fit it into a mid-engined car. It might have been achievable, but even if the packaging were possible, such a feat would have sent the price well over £100k and into 911 GT3 territory.

A 4.0-litre flat six for the new 2019 Porsche 718 Cayman GT4

The 4.0-litre is not, though, simply an enlarged version of the naturally aspirated 3.8-litre Carrera S engine (from the Gen 1 991) that powered the first Cayman GT4 and last-gen Spyder. Instead it’s an enlarged but naturally aspirated version of Porsche’s latest turbocharged flat-six. Or for those of you into your engine codes, the old engine was from the ‘9A1’ family, the new one is a derivative of the ‘9A2 Evo’ (which is from the latest 992-generation 911). 

Porsche hasn’t divulged the full technical details yet, but a large portion of the engine is new and specific to the 718 GT4 and Spyder. ‘It’s a new 4.0-litre, almost a blank sheet,’ Andreas Preuninger revealed to CAR magazine. ‘It has roughly the same stroke and bore as the GT3, but it is more a derivate of our turbo engine.

'It spins to 8000rpm, so the redline is higher than before, and it’s got loads of torque because it’s a 4.0-litre. There’s an integrated dry sump. There are some similarities with the 9A2 Evo, like the plastic oil pan to reduce weight, but so much is new. It’s almost a completely new design. The crankcase, cylinder head, intake manifold – we really tried to design a unique engine.’ 

What about the noise of the new 718 Cayman GT4? 

You mean does it have a particulate filter? Well, it does, no other way around it, and we haven’t heard the new motor running yet so can’t comment on the sound. Though best prepare yourself for how it sounds on three cylinders too, as under part-load Porsche’s adaptive cylinder control temporarily interrupts the injection process in one of the cylinder banks to reduce consumption. There’s also start-stop, for the first time in a Porsche GT car.

Front of the new Cayman GT4: the purest mid-engined Porsche yet?

But every cloud has a silver lining. Says Preuninger: ‘It’s street-legal for years, as it has a particulate filter, one on each side – it has to have them. And it can be built on the 9A2 production line, unlike the GT3 engine. One thing we learned from the last GT4 is a lot of people couldn’t get one. Now we’re really proud enthusiasts can buy the car, rather than write letters. We’re not limited in a way, we will have a longer production run than before, and we wanted to keep it in the same price range.’

UK prices

In short, the new 718 GT4 might not sound as good as the last one, but Porsche can build more of them, for more years. As for the cost, prices start at £75,348 for the 718 Cayman GT4, while the 718 Boxster Spyder is £73,405. 

That’s more than the bargains of £65k and £60k they were before, but not the rumoured £90k prospective owners were worried about.

I want all the gossip – what about the rumours of a turbocharged engine in the new Porsche GT4?

If you want further detail, the new motor hasn’t actually been engineered by the Porsche Motorsport team who create the high-revving GT3/GT3 RS engines, but by the main Porsche development hub. And before you scoff, that’s the same team that gave us the 691bhp twin-turbo engine in the GT2 RS, so they have pedigree. 

Side profile: the new 2019 Porsche 718 Cayman GT4

Alternatives? Not really. The old naturally aspirated 3.8 wouldn’t have met emissions regulations, so that was never going to be seen again (though it lives on in the 718 GT4 race car). As for turbo engines, a more powerful version of the 2.5 four-cylinder from the 718 Cayman wouldn’t have actually made the power needed, and dropping in the turbocharged 3.0 flat six from the 992 would have been overly complicated, not least because of all the heat that would have needed to be evacuated. 

Crucially, Porsche wanted to keep the GT4 and Spyder free of turbos. ‘The GT4 and the Spyder were so successful, and one reason was the atmospheric engine,’ smiles Preuninger. ‘We love the purity and simplicity of normal aspiration. An atmospheric engine paints a grin on your face, we know how to do that. Our heart beats for high-revving, naturally aspirated engines. We’re doing it all the more.’

There wasn’t much wrong with the first Cayman GT4, so what’s changed for 2019?

‘I read all the old press tests of the 981-generation GT4,’ says Preuninger. ‘And the only criticism was the gear rations. They’re the same for emissions homologation, we can’t change that, but we have a 4.0 with more torque to address that.’ 

Side profile: the new 2019 Porsche 718 Cayman GT4

The torque peak output is actually unchanged, remaining at 310lb ft, but it’s now delivered from 5000 to 6800rpm compared to the 4750-6000rpm of old – and hopefully with a lot more lower down the rev range too. 

As for the rest of the 718 GT4 package, the suspension is still derived from the GT3’s – but this time from the 991 Gen 2 model rather than the 991 Gen 1 as before. PASM adaptive dampers are standard, the GT4 sits 30mm lower than a regular 718, and you can adjust the toe, camber and anti-roll bars. 

Anything else?

The rest is gentle evolution, rather than revolution, to ensure the Cayman GT4 still strikes a perfect balance on road and track, still stays true to the same philosophy of putting a smile on your face rather than being quickest at a track day. 

Porsche Motorsport always seems only to tinker, yet their little changes add up to a lot. Case in point, the Nürburgring Nordschleife time is claimed to be reduced by more than 10 seconds, to a sub 7min 30sec lap.

Porsche 718 Cayman GT4 interior

Other stuff? The exhaust is switchable, the steering wheel is wrapped in Alcantara and measures a slinky 360mm in diameter, and there’s a button to engage (or disengage) the auto blip function. Options include the PCCB ceramic brake system, carbon bucket seats, and a Club Sport Package with a rear cage, fire extinguisher and six-point harnesses for the driver.

What chance PDK, a Touring model or an RS?

Given a manual box is standard, there’s not a lot of scope for differentiating a Touring model, and Preuninger isn’t interested in doing that just for the sake of it. ‘The GT4 does everything so good, so what would a Touring be? The same car without a wing? Does that justify a whole new model? The GT4 is already more like a Touring with a wing. I like to have credibly different products.’ 

As for PDK though… ‘I would lie to you if I said we didn’t discuss this, and maybe later in the lifecycle we are bringing a variant with PDK.’

Serious lightweight bucket seats for GT4

Reckon on that being a GT4 RS, with more power too. Why? ‘We think with this engine we can do something more in the future as well…’

Performance specs and downforce data?

The aero package on the GT4 is pretty serious, designed to squash this Cayman into the tarmac for even stickier handling. Overall there is about 50% more downforce than before, which puts it in the GT3 bandwidth [circa 150kg at high speeds]. And if you’re not a fan of the diffuser, just keep in mind that’s where 30% of the downforce now comes from on this car. 

The new Porsche 718 Cayman GT4 has a top speed of 188mph, sprints from 0-62mph in just 4.4 seconds and return 25.7mpg on the WTLP combined cycle. The kerbweight is up, from 1340kg to 1420kg, because Porsche, like all other manufacturers, now has to homologate its cars without any options selected. Meaning they don’t get weighed with carbon buckets or brakes. 

Rear wing on new Porsche 718 Cayman GT4

But while there is some actual extra weight in the car (the diffuser is about 6 or 7kg more, the new particulate filter around 11kg, and a bigger starter motor and a bigger battery are part and parcel of meeting the new emissions regulations) Preuninger promises it’s not as bad as it seem: ‘I can assure you, it doesn’t feel even half a gram heavier.’

Be sure to sound off on the new 2019 Porsche 718 Cayman GT4 in the comments below

The race one: Porsche's 718 Cayman GT4 Clubsport track special

The Clubsport one

Porsche’s track-day Cayman has returned. The new 718 Cayman GT4 Clubsport has been designed as a ‘near-standard’ racer for rookies and professionals alike, and was unveiled earlier in 2019.

There are two versions of the GT4 Clubsport: ‘Trackday’ and ‘Competition’. The former has fixed shocks, electronic driving assistance aids (that can be switched off), air-con and a handheld fire extinguisher. The fiercer model has three-stage adjustable shock absorbers, a quick-release racing wheel, adjustable brake bias, a larger fuel tank and an automatic fire extinguisher system. Neither is road-legal.

Cayman GT4 Clubsport rear cornering

The juiciest bit? While the current pack of 718 road cars only use flat fours, this racer has a naturally-aspirated 3.8-litre flat-six, capable of 419bhp and 313lb ft. Drive goes to the rear wheels via a six-speed race-spec PDK, and other tasty performance parts include a reinforced dual mass flywheel and FIA-spec parts so it’s fit for racing.

Want one? The rookie version is priced at €134,000 (£120,435) before taxes while the Competition version will set you back €157,000 (£141,082) before taxes.

We drive Cayman GT4 Clubsport

Check out our Porsche reviews

By Ben Pulman

CAR's editor-at-large, co-ordinator, tallboy

Comments