Porsche Cayman GT4 PDK 2021 Review

Believe it or not, a small, loyal following of Australian Porsche enthusiasts has been waiting six years for the 2021 Porsche 718 Cayman GT4 PDK.

While the original 981-series Cayman GT4 (2015-2019) employed a 3.8-litre naturally-aspirated flat six to become Porsche’s quickest and fastest mid-engined model, the latest third-generation 982-series Cayman (which along with the fourth-generation Boxster was renamed the 718) upped the ante with a bigger 4.0-litre atmo boxer six for last year’s new GT4, but it remained available only with a six-speed manual gearbox.

Now, along with the 718 Spyder and the 718 Boxster and Cayman GTS 4.0 models, the Cayman GT4 brings an automatic transmission for the first time.

The highly-anticipated option of the seven-speed dual-clutch gearbox not only increases the straightline speed of the mid-engined two-seat 2021 Porsche 718 Cayman GT4 PDK, but significantly broadens its appeal.

Manuals are increasingly uncommon on the performance car scene, but have been a staple in the Porsche community for decades and will apparently continue to be.

Does the automatic version of Porsche’s most formidable mid-engined sports car – dilute the GT4’s raw, visceral and purist appeal?

We ventured to one of the world’s greatest driving meccas – Tasmania – to find out.

It might be the German sports car brand’s most affordable GT model, but the 2021 Porsche Cayman GT4 is still a $200,000-plus proposition – and the new PDK automatic variant commands a $5090 premium over the manual at $210,200 plus on-road costs.

That puts it within cooee of the base 911 Carrera PDK ($236,300 plus ORCs), but it’s worth noting that a slightly less powerful (294kW) version of the same 4.0-litre atmo-six powers the slightly less focussed Cayman GTS 4.0 PDK and manual for almost $35K less – from $172K plus ORCs.

And the GT4 is still a lot cheaper than the new $370K 911 GT3, the previous generation of which donated much of its powertrain and front suspension technology.

Irrespective of its sporty position at the top of Zuffenhausen’s mid-engined model tree, the Porsche Cayman GT4 offers its fair share of creature comforts and modern touches.

There are tinted bi-xenon headlights with cornering function (LED headlights are optional), LED front running lights with direction indicators, LED tail-lights, auto-dimming rear-view and side mirrors, dual-zone climate control, heat-insulating glass, electric sports seats furnished in Alcantara, and heating for the seats and steering wheel.

Infotainment is facilitated by a crisp centre touch-screen offering Apple CarPlay (no Android Auto), digital radio and sat-nav, while the instrument cluster is a neat combination of a large central analogue tacho and a 4.6-inch digital display conveying key trip, nav and infotainment data.

There are no steering wheel buttons or driver safety aids like autonomous emergency braking, lane-keeping or blind-spot monitoring – just twin front and side airbags, stability control and anti-lock brakes.

But you can add a roll cage and big ceramic brakes (PCCB), which are just two of many optional extras available.

Our tester was fitted with a laundry list of options that ballooned its price to $239,750 plus ORCs. They included a $6070 Python Green paint scheme, a $3320 leather interior, $4630 adaptive sports seats and a $2230 BOSE surround sound system.

The 2021 Porsche Cayman GT4 is covered by a relatively short three-year factory warranty in Australia, servicing intervals are 12-month/15,000km and there is no independent crash safety rating.

It goes without saying the 2021 Porsche Cayman GT4 PDK is focussed. So focussed that its standard rear splitter contravenes Australian Design Rules.

See, our occasionally nanny-like ADR laws decree a minimum 100mm clearance between a vehicle and the underlying terra firma. That meant Porsche engineers had to construct a new rear splitter with smaller veins especially for the Australian market.

It’s a small detail, but one that demonstrates the level of track-ready pedigree on offer here. Elsewhere, there’s front suspension adapted from the 911 and a rear wing with spanner adjustment.

But the star of the show remains the Cayman GT4’s prodigious big-bore boxer engine: a bustling 4.0-litre naturally-aspirated flat-six.

Maximum power is advertised at 309kW at 7600rpm and peak torque at 430Nm (10Nm more than the manual) at 5500rpm – rather than over 5000-6800rpm.

We say advertised because we wouldn’t at all be surprised if the actual figures exceed those numbers. As is the Porsche way.

Similarly, take the 0-100km/h times with a grain of salt. With PDK on board, Porsche says the Cayman GT4 PDK is half a second quicker than the manual to 100km/h, reaching the mark in 3.9sec (versus 4.4) on its way to 200km/h in just 13.4sec (v 13.8) and a top speed of 302km/h (down from 304km/h for the manual).

As we expected, that makes the GT4 PDK quicker than the latest 992-series Porsche 911 Carrera, which is powered by a 331kW 3.0-litre twin-turbo six-cylinder boxer engine and standard eight-speed PDK, and is claimed to hit 100km/h 4.2sec and 200km/h in 14.5sec.

But the bigger news here is flexibility. Porsche says the GT4 PDK’s 80-120km/h in-gear acceleration time is just 2.5 seconds – a fraction of the 6.0sec it takes the overly tall-geared manual in fifth gear.

This is despite the PDK-equipped Cayman GT4 imposing a 30kg weight penalty over the equivalent manual: 1420kg (unladen) versus 1450kg.

While the GT4’s engine offers a solitary angry setting, the dampers can be configured two ways, and the chassis geometry can be manually tweaked either via toe, camber or anti-roll bars. Active transmission mounts are also part of the standard fare.

All this chassis goodness connects to the road via super-sticky Michelin Pilot Sport Cup 2 tyres measuring 245/35 ZR20 up front and 295/30 ZR20 at the rear. The 380mm brake discs are clamped by six-piston front callipers and four-piston rears.

The GT4 gets a full-panelled flat underbody, NACA inlets and a new diffuser inspired by the Porsche 911 RSR wide-body endurance race car. It also gets a sports exhaust with dual outlets.

Very focussed indeed.

Tasmania’s incredible road network is a juicy prospect for any car enthusiast and a match made in heaven for the Porsche Cayman GT4 PDK. But the twisting rural roads through spectacular scenery are even better when they’re closed off.

That’s exactly what was available to carsales last week when we participated in the 2021 Porsche Targa Tasmania Tour.

Ordinarily attached to a $12,000 entry fee for well-heeled Porsche owners (the cost covers driver and passenger using one vehicle), the Targa Tour is a six-day, 36-stage event covering more than 2000km of intense driving.

For the GT4, Targa is the perfect way to exploit its superlative grip levels, mid-engine poise and high-speed corning and braking prowess.

Furthermore, a 130km/h speed ceiling (imposed by a Rally Safe box that is tracked by Tour officials) makes the GT4 PDK’s powertrain well suited, too: it’s fast enough to maintain a challenging pace in the tighter turns and most straights, and to explore the Cayman’s circa-7800rpm limit without breaking the rules.

It was also the ideal location in which to test what’s new here: the PDK transmission. Unsurprisingly, it’s a cracker, offering whip-like shifting expediency, a terrific (and compared with the manual, more useable) spread of ratios and typical Porsche polish in all scenarios.

In daily conveyance, the PDK offers relatively smooth passage. Despite its higher torque capacity and performance capability, it largely avoids the tendency to grab and jolt during take-off and low-low speed manoevring – a trait that tends to afflict most other dual-clutch gearboxes.

Low-speed changes are smooth and well-timed, and other than an occasional shunt upon stepping on the accelerator, this mid-engined application feels as slick as the PDK in any 911. Open-road touring is better facilitated than the close-ratio manual equivalent; revs are held closer 2000rpm, rather than 3000rpm in the stick-shift.

That said, the biggest benefit, not surprisingly, comes on Tassie’s extensive ribbons of back-roads. There, the PDK is a star, helping the atmo engine find a natural cadence in the middling revs to provide tractable and explosive go-forward.

The PDK’s ratios are terrific for Targa driving, allowing the vehicle to spend most of its time in second and third gears, where power and torque is immediate and accessible.

The PDK Sport setting elicits sharper shifts again, streamlining the process of navigating the at-times greasy and treacherous roads underneath.

The discordant combination of a mechanical, raucous rasp remains the GT4’s distinctive feature and helps distinguish it from a legion of other similarly focussed rivals.

The 4.0-litre engine revs freely and willingly, and is simply a joy to engage with in both high-speed or low-speed scenarios.

Equally, we were surprised at the fuel use of 13.4L/100km in predominantly heady proceedings.

About the only asterisk in the GT4’s dynamic repertoire relates to tyres – especially in Tasmania during April. The Cup 2s require heat generation to perform as intended. This is not a complaint as much as an observation: generate heat first and you’re on the way to sticky, predictable tyre nirvana!

As ever, feedback is a core strength in the GT4’s arsenal. It is an intimate and articulate affair, telegraphing underlying movements, grip levels and yaw in a manner that breeds confidence. You feel as though you can put out figurative spot fires in an instant, usually by unwinding some lock or steadying your inputs.

Failing that, the electronic nannies intervene as a matter of course, doing their thing effectively yet benignly, so as not to wash off too much progress.

Elsewhere, there are some minor telltale details giving away the car’s ‘GT’ brief, like a stiff ride, some vibration and ever-present road noise.

Remarkably, the ride takes the edge out of most bumps to deliver comfort levels that often exceed some modern hot hatches. There is rarely any thudding as a consequence, and body control is remarkable over broken bitumen.

Likewise the steering is light at low speeds but superbly weighted and precise at pace, there is ample outward vision and the well sorted pedal modulation and intuitive controls make navigating car parks and low-speed manoeuvres a cinch.

The downsides of the best part of a week in Porsche’s mid-engine maestro?

Storage is limited with people on board: there are narrow door pockets, the centre console is tiny and hard to access and the pop-out cup-holders are flimsy.

That said, there’s a 150-litre ‘frunk’ and 270 litres of storage behind the seats, including a pair of closed cubbies with sliding doors.

The truth is the PDK transmission only enhances the considerable performance of the Porsche Cayman GT4 – and it does so without diluting driver engagement.

Want proof? We were happy to forego the manual GT4 variant at Targa in favour of the auto, which was not only easier and more convenient to drive, but easier to drive faster and more confidence inspiring on treacherous roads.

So for those patiently waiting for a PDK option over the past six years, the wait has been well and truly worth it.

But please, Porsche, continue to offer us a manual option in the future as well.

How much does the 2021 Porsche Cayman GT4 PDK cost?
Price: $210,200 (plus on-road costs)
Available: Now
Engine: 4.0-litre six-cylinder petrol
Output: 309kW/420Nm
Transmission: Seven-speed dual-clutch automatic
Fuel: 10.4L/100km (ADR Combined)
CO2: 238g/km (ADR Combined)
Safety rating: Not tested

Related: Porsche Cayman GT4 International Review
Related: Porsche Targa Tasmania - The ultimate road adventure

Tragedy struck the 2021 Targa Tasmania with the death of three competition entrants in two separate incidents. carsales extends its sympathies and condolences to the family and friends of the persons involved.