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It’s fair to say that the Porsche Cayman GT4 RS has been one of the most talked about cars in recent years. The GT4 RS represents the Porsche Motorsport Department applying all of their knowledge and skill to create the ultimate Cayman. With the next generation of Boxster/Cayman looking likely to be fully electric, the GT4 RS stands as the last of the internal combustion powered mid-engined Porsche sports cars.
Almost straight from the South Lakes Porsche Dealership, one of the first UK registered GT4 RSs came through the workshop the other day. This Jet Green Metallic car came to us for a full Porsche set up and for the installation of some Pagid RSC1 brake pads in preparation for an upcoming track day.
With the GT4 RS on the ramp we had plenty of time to have a look at the underside and to see what changes Porsche had made over the 718 GT4.
As standard, the Porsche ‘GT’ cars, which includes the 911 GT3/RS, the GT2RS and the Cayman GT4/RS have a good amount of adjustability from the factory. Using basic tools, you can adjust the front and rear camber settings, the front and rear toe settings, the ride heights and the front and rear anti-roll bars feature multiple holes to adjust their stiffness.
GT Porsches have significantly more points of adjustment than the vast majority of road cars, and this adjustability works as a great basis for many different types of setups, although they can be made better.
Front Suspension
The front suspension of the Cayman GT4 RS is a hybrid blend comprising mainly from the front suspension of the 991.2 Porsche 911 GT3 and GT3 RS.
Unlike the latest 992 GT3, which has a double wishbone front suspension assembly, the GT4 RS retains the MacPherson Strut design found on the 991.2 GT3 RS. The MacPherson strut is a simple and effective system which is also incredibly compact, making it ideal for a small sports car such as the Cayman.
The shocks and springs on the GT4 RS are Bilstein units, and the springs are stiffer than those on the standard Cayman GT4. The GT4 RS also has helper springs located atop the main springs which help to keep the main springs under tension even during severe wheel deflection, such as when running kerbs on the race track.
The bushes in the front axle suspension assembly are all solidly mounted to prevent any unwanted flex and geometry changes during hard driving, and any bearings are spherical motorsport monoballs.
The GT4 RS retains the camber adjustable top mounts/camber plates that are found on all Porsche ‘GT’ cars, and the front ride height and toe settings are also fully adjustable.
Compared to the 718 Cayman GT4, the GT4 RS has a six millimetre wider front track and bespoke carbon fibre quarter panels to accommodate this wider track width. These quarter panels feature vented slats at the top of the wheel arch which helps to prevent high-pressure air collecting in the front wheel arches. This reduced air pressure in the wheel arch reduces front lift and helps the GT4 RS cut through the air more effectively. The trailing edge of the front wheel arch is cutaway featuring a very soft radius design to help reduce drag and to ensure smooth airflow around the wheels and down the flanks of the car.
Rear Suspension
The rear suspension of the Cayman GT4 RS is very similar to the setup found on the standard 718 Cayman GT4. Rear camber and toe angles are fully adjustable, as is the rear ride height and anti roll bar. As with the front suspension, the GT4 RS features uprated Bilstein dampers and stiffer springs and helpers to improve body control and responsiveness.
The rear toe adjustment arm on the Cayman GT4 RS is slightly different to the one found on the standard 718 Cayman GT4, with the GT4 RS’ arm offering a greater range of adjustment. This enables more aggressive rear axle settings to be applied for improved performance.
The Cayman GT4 RS features an eight millimetre wider track than the 718 Cayman GT4 for improved traction and stability, and the GT4 RS also features a fully adjustable rear anti-roll bar. Interestingly, this GT4 RS was equipped with the Weissach Package, which includes a number of weight saving items, yet the GT4 RS lacks the carbon fibre front and rear anti-roll bars as seen on 991.2 GT3 RS that are part of the Weissach Package for that model.
The rear bodywork of the Cayman GT4 RS is notable for featuring a swan-neck rear wing, much like the 992 generation Porsche 911 GT3. This design allows air to flow more freely under the wing which reduces drag.
The rear wing on the Cayman GT4 RS is significantly more adjustable than the wing found on the standard 718 Cayman GT4. The GT4 RS’ rear wing is also mounted further forward, which increases the amount of air that is channelled over and under it, increasing downforce.
To conclude,
The suspension system of the Porsche Cayman GT4 RS is a mix of the suspension from the 991.2 generation Porsche 911 GT3 RS and the Porsche 718 Cayman GT4. Like many of Porsche’s most revered road cars, the GT4 RS represents the culmination of many small changes as opposed to any drastic modifications. Whilst we were left a little disappointed by the lack of bespoke hardware, the effect of the changes Porsche has made are undeniable as the Cayman GT4 RS stands proudly as one of the greatest mid-engined sports cars of all time, and the greatest ever Porsche Cayman.
Get in touch.
If you would like your GT Porsche setup to be optimised for fast road or track use to unlock the full potential of your car then get in touch with our team via phone at 01565 872834 or via our contact form.
