Porsche Cayman GT4 type 981: the purist's choice, the exhaust system guide
The Cayman GT4 type 981 was welcomed as a gift to purists: mid-mounted engine, manual gearbox, a chassis developed by the GT department and a 3.8-litre naturally aspirated flat-six with 385 hp. Everything in this car is geared towards sensation, except the factory exhaust, which filters the engine as much as it weighs it down. This guide takes you through choosing the ROG valved exhaust for your GT4, from material to fitting.
Written by ROG Motorsport · Updated

Your ROG exhaust for the Porsche Cayman GT4 type 981
From €3,990 in stainless steel, €4,990 in titanium
Configure my exhaust- Vehicles
- Porsche Cayman GT4 3.8 type 981 (2015-2016)
- Engine
- 385 hp · 420 Nm
- Exhaust
- Valved cat-back, built for your VIN
- Material
- 304 stainless steel or titanium
- Front section
- Optional: catted manifolds with 200 or 100 cells, or decat
- Valves
- ROG remote, or factory control if your vehicle has it
- Lead time
- 20 working days from order confirmation to delivery
- Warranty
- 3 years, parts and workmanship
Closely related versions have their own guide: Porsche Boxster / Cayman 2.7 type 981, Porsche 718 Boxster / Cayman 2.0 turbo type 982, Porsche 718 Boxster GTS 2.5 turbo type 982, Porsche 718 Cayman GT4 4.0 type 982.
The naturally aspirated 3.8 flat-six: the heart of the Cayman GT4 type 981
The Cayman GT4 type 981 gets a 3.8-litre naturally aspirated flat-six, mid-mounted just behind the seats. It produces 385 hp and 420 Nm. Without forced induction, it responds instantly to the throttle and gathers revs with a linearity that makes the driving so rewarding, especially paired with a manual gearbox and such a precise chassis.
On a naturally aspirated engine like this one, the exhaust shapes a large share of the sensations: it accompanies every climb through the revs and every downshift. The GT4's factory exhaust filters a great deal and adds weight at the rear. The lighter ROG valved exhaust gives you back the voice of the flat-six when you want it, and quieter running with the valves closed, without touching the engine or the ECU.
What makes up the exhaust on your Porsche Cayman GT4 type 981
An exhaust system is best understood in two parts. Here is what each one does, and what ROG replaces.
The cat-back is the complete exhaust system
It is everything you can see under the chassis of your Porsche Cayman GT4 type 981, from the outlet of the front section to the tips: pipes, silencer, valves. Routing, silencer, valves: this is where the sound is shaped, and where we focus our research and development.
The front section, where the catalytic converter sits
On your Porsche Cayman GT4 type 981, that means the manifolds, which collect the gases as they leave the cylinders. The factory catalytic converter is built into it: the second restriction in the exhaust, after the silencer. Changing this part remains a choice: it pays off mainly with an ECU remap, which turns the freed-up flow into power.
The figures for your Porsche Cayman GT4 type 981
What an exhaust changes straight away is the sound, the engine's breathing and the weight at the rear. For more power, add an ECU remap.
Power
Torque
Published factory and Stage 2 figures.
With or without an ECU remap, the exhaust fits and works. But it is an ECU remap at an approved tuning centre that truly unleashes your Porsche Cayman GT4 type 981, and that is what we recommend.
Being naturally aspirated, the GT4's 3.8-litre does not have the headroom of a turbo engine: a Stage 2 remap adjusts ignition and injection for more modest gains. The ROG exhaust is its natural complement, showcasing what the flat-six has to say at high revs.
Configuring your exhaust, step by step
3 choices, in the same order as the product page configurator.
-
Step 1 of 3: Material: stainless steel or titanium
For your Porsche Cayman GT4 type 981, the exhaust costs €3,990 in stainless steel and €4,990 in titanium.
304 stainless steel
3 990 €
- Weight
- Baseline
- Sound
- Full and rounded
Durable, corrosion-resistant, with a rounded, full sound: the most popular option.
Titanium
4 990 €
- Weight
- Around 40% lighter
- Sound
- Metallic, crystal-clear
For the same design, it weighs around 40% less than stainless steel. A more metallic note at high revs and a look all of its own, from brushed to blued.
Both materials age well: 304 stainless steel copes with winter and salt, and titanium does not rust. Stainless steel or titanium: what really changes.
-
Step 2 of 3: Front section: manifolds and catalytic converter
Optional: the manifolds on your Porsche Cayman GT4 type 981, with the catalytic converter. Sound rating out of 10, valves open: the factory exhaust sits at 3.
Cat-back only
Included
7/10Factory emissions control
Nothing changes at the front: the cat-back alone is already enough to change the car.
200-cell sports catalytic converter
+1 420 €
8/10Road use and French MOT
The everyday compromise: emissions control is still there, and breathing improves noticeably.
100-cell sports catalytic converter
+1 420 €
9/10French MOT pass not guaranteed
One step further: more flow, a more aggressive sound, reduced emissions control.
Decat
+920 €
10/10Track use only
Everything unleashed: maximum flow and unrestrained sound, for the track.
Sound intensity, on a scale of 0 to 10
- 10/10Decat manifolds + ROG cat-back
- 9/10100-cell sports catalytic converter + ROG cat-back
- 8/10200-cell sports catalytic converter + ROG cat-back
- 7/10ROG cat-back only, factory catalytic converter retained
- 3/10Factory exhaust, for comparison
Valves open. With the valves closed, every configuration becomes discreet again.
What about the engine warning light? It can appear with a sports catalytic converter: the downstream oxygen sensor reads a different level of cleaning from the factory unit. It is not an engine fault, and it is dealt with by an ECU remap or a diagnostic tool. With a decat, an ECU remap becomes necessary. If it happens to you, call us and we will point you in the right direction. Passing the French MOT with a sports exhaust.
-
Step 3 of 3: Valves: ROG remote or factory control
Two ways to control the valves on your Porsche Cayman GT4 type 981.
ROG remote

The simplest solution: a control unit in the boot and a remote, open or closed at the press of a button, whatever mode you are in. A question while fitting? We will get back to you.
Factory control
- Only for vehicles fitted with factory valves
- Controlled by the drive modes
Does your vehicle have factory valves? The exhaust keeps their existing control: the drive modes operate the valves, as before, with no added electronics.
On a long journey, what matters is the absence of drone at a steady speed. With the valves closed, the exhaust keeps the cabin calm; the show is still there whenever you ask for it. More about exhaust drone.
The ROG sound signature on the Cayman GT4's flat-six
The GT4's naturally aspirated flat-six has a racing voice: gruff and metallic in the mid-range, then increasingly piercing towards the rev limiter. Sitting just behind you, it ought to fill the cabin; yet the factory exhaust holds a good part of it back, especially outside the car.
With the valves open, the ROG exhaust lets the flat-six howl freely at high revs, with more vocal downshifts punctuating every braking zone. With the valves closed, the GT4 is more discreet, for driving to the circuit or passing through a village without turning every head.

From order to fitting
-
Configuration
You choose the options for your Porsche Cayman GT4 type 981 and enter its VIN, found in box E of the registration certificate.
-
Check
We confirm compatibility with your car before we build it.
-
Manufacturing
Made to order, for your Porsche Cayman GT4 type 981.
-
Delivery
Free, insured delivery, with tracking sent on dispatch.
-
Fitting
Clamps and gaskets, no welding: two hours on average at the garage of your choice.
20 working days from order confirmation to delivery
- Warranty
- 3 years, parts and workmanship, from the date of delivery
- Payment
- In instalments with Klarna
- Installation
- At the garage of your choice
What about the manufacturer's warranty? In Europe, fitting a part from another brand is not enough on its own to void it; the manufacturer has to prove the link between that part and the fault. Our article on the manufacturer's warranty.
Our recommendations for your Porsche Cayman GT4 type 981
-
Daily driving
3 990 €
- Stainless
- Cat-back only
- ROG remote
Your Porsche Cayman GT4 type 981 stays easy to live with, the factory emissions control is retained, and you open the valves whenever you choose.
View this configuration -
Fast road
6 410 €
- Titanium
- 200-cell manifolds
- ECU remap
For great roads: more voice and more response, while staying road-friendly.
View this configuration -
Track
5 910 €
- Titanium
- Decat manifolds
- Stage 2
The most extreme configuration, for track use only.
View this configuration
These profiles are starting points. The right choice is often made in five minutes on the phone.
Porsche Cayman GT4 type 981: your questions
How much power does an exhaust system add to the Porsche Cayman GT4 type 981?
From the factory, the Porsche Cayman GT4 type 981 produces 385 hp and 420 Nm. Without a remap, the exhaust transforms the voice and lightens the rear; it is the ECU remap that increases power. With a Stage 2 build, the published figures reach 425 hp and 462 Nm.
Stainless steel or titanium: which material for the Porsche Cayman GT4 type 981?
For the Porsche Cayman GT4 type 981, the ROG exhaust costs €3,990 in stainless steel and €4,990 in titanium. Choose stainless steel for value for money and a rounded sound, titanium to save around 40% in weight and get a clearer tone.
Do you need to replace the catalytic converter on the Porsche Cayman GT4 type 981?
No, the cat-back alone already does most of the work on the Porsche Cayman GT4 type 981. The manifold option is for those tuning the engine: 200 cells to stay road-friendly, 100 cells or decat for the track.
Does the Porsche Cayman GT4 type 981 pass the French MOT with a ROG exhaust?
The cat-back only and the 200-cell sports catalytic converter both keep emissions control: that is the configuration to present, with the valves closed. The 100-cell converter makes a pass uncertain, and with the decat the Porsche Cayman GT4 type 981 fails the emissions test.
How is the ROG exhaust fitted to the Porsche Cayman GT4 type 981?
Fitting needs no welding or cutting and takes two hours on average on a lift. We check compatibility with the VIN of your Porsche Cayman GT4 type 981 before manufacturing.
What does a ROG exhaust for the Porsche Cayman GT4 type 981 cost, and how long does it take?
From €3,990 to €6,410 depending on the configuration. Allow 20 working days from order confirmation to delivery. Free delivery in Europe, 3-year warranty.
Unsure about your configuration? Give us a call.
Between stainless steel and titanium, between the cat-back only and the full system, the right choice depends on how you drive and on your Porsche Cayman GT4 type 981. We take the time to talk it through before you order, with a reply within 24 hours. We are not here to sell to you over the phone: we help you choose, even if that means a cheaper option because it suits the way you drive.
Behind every ROG exhaust is a French team you can actually reach, who know the cars they talk about. More than 500 exhaust systems fitted and a rating of 4.9 out of 5.
Further reading
- All Porsche exhaust systems
- Porsche Boxster / Cayman 2.7 type 981
- Porsche 718 Boxster / Cayman 2.0 turbo type 982
- Porsche 718 Boxster GTS 2.5 turbo type 982
- Exhaust diameter: bigger does not mean more powerful
- Passing the French MOT with a sports exhaust
- Stainless steel or titanium: what really changes
- The 22 brands we cover
Read next
- Porsche Panamera 976 V6 biturbo: a GT that asserts itself, the exhaust system guide The Panamera type 976 opens the third generation of Porsche's grand tourer, and its entry-level version relies on...
- Porsche Panamera Turbo S E-Hybrid 971: the V8 comes to the surface, the exhaust guide The Panamera Turbo S E-Hybrid 971 combines a 4.0-litre twin-turbo V8 with an electric motor, for a combined...
- Porsche Panamera 971 V8 biturbo: a big GT that rumbles, the exhaust system guide The Porsche Panamera 971 combines the space of a large saloon with the performance of a sports car,...