Introduction
An upgraded exhaust system is one of the best mods for bringing out the feral side of your GTI.
It’s not all just about the exhilarating soundtrack and aggressive rumble that an aftermarket exhaust produces, but also the increase in performance.
Knowing which sections of the exhaust to upgrade to achieve your goals and what products to pick is crucial.
We’ll first take a quick look at the different sections of the MK5 GTI’s exhaust to give you a better idea of what upgrading each section will do.
Then we’ll show you the best quality exhaust upgrades out there that cater to all budgets.
Let’s get into it!
Exhaust Sections
The GTI’s exhaust system is made up of a few different sections, each presenting a unique opportunity for enhancement.
Understanding what each section is responsible for will help you make the best informed decision when shopping exhaust systems.
Let’s start looking at the start of the exhaust near the engine where we have the downpipe.
This is one of the best sections to upgrade if you are after additional power.
A larger diameter downpipe can help enhance the turbo’s performance by reducing back pressure, leading to quicker turbo spool, improved throttle response, and a noticeable gain in power.
After the downpipe we have the catalytic converter. Although an essential component for emission laws, it can be restrictive and cost you power.
An alternative is to fit a high flow sports catalytic converter which will keep the car compliant for emission tests while also optimising performance. A non road-legal alternative is a decat pipe which is a simple straight pipe which bypasses this section.
Lastly, we have the backbox/muffler section. This section is responsible for controlling sound. Many exhaust manufacturers refer to this section as the cat-back and this section can also include a resonator.
Performance cat-back’s can produce a deeper, more pleasing exhaust note, and often utilise better flowing designs which can help squeeze out a little extra performance too.
To summarise, if it’s primarily sound you are after – opt for an aftermarket cat-back system.
If it’s performance, go for a larger downpipe and high flow sports cat first.
Now we’ve covered all that, let’s start looking at the best products.
Pipewerx Downpipe & Sports Cat
This is a great option if you are looking for a high quality performance upgrade for your exhaust system.
Pipewerx are a reputable manufacturer in the UK VW scene for their high quality exhaust system builds and great fitment.
This 3 inch downpipe expands on the OEM downpipe diameter, and is mated to a 200 cell high flow sports cat to maximise performance.
This is the perfect upgrade when going for a Stage 2 remap, and can produce up to a 10% increase in power!
Undoubtedly a fantastic option for extracting as much performance as possible.
They recommend upgrading your lower engine mount when fitting this system.
Milltek Downpipe & Sports Cat
You can’t go wrong with Milltek, and the same is true for this exhaust system for the MK5 Golf GTI.
Like the above downpipe, this is a 3 inch bore to allow for maximum exhaust gas flow and reduced backpressure.
This is also paired to a 200 cell sports cat to remain road legal while providing performance gains.
This system is designed to fit to other 2.75 inch Milltek cat-back systems, so won’t fit to the standard cat-back.
An uprated lower engine mount is also recommended.
Performance Motorsport Decat Pipe
As an alternative to a sports cat, you can use a decat pipe to bypass the standard catalytic converter.
This can free up power as well as boost your exhaust tone.
The main drawback with this for most people is that it isn’t road legal as you won’t pass emission tests.
As such, they are sold for track use only.
Scorpion Non Resonated Cat-Back
The Scorpion exhaust systems are extremely popular among MK5 GTI enthusiast owners for their fantastic sound and quality.
Their non resonated cat-back is the perfect upgrade if you are wanting a deeper and sportier sound from your tailpipes.
This has been designed to mate up with either the standard catalytic converter or other Scorpion sections.
This diameter is 3 inches and comes with lovely polished looking exhaust tips.
As this system does away with the resonator, it will be a fair bit louder than the standard system. If you have an upgraded downpipe and sports cat, this may be too loud for some owners. If so, you may wish to opt for the resonated version of this exhaust which we’ll cover next.
Scorpion Resonated Cat-Back
The resonated version of the Scorpion exhaust brings a nice sportier rasp to the exhaust tone without being too overbearing. This is perfect if you are looking for some more sporty subtlety.
This will be compatible with the standard catalytic converter or other Scorpion exhaust sections.
If you have an upgraded downpipe and sports cat, then this can be the perfect level of sound for many owners.
Gravity Cat-Back
The Gravity cat-back is a more affordable option for those looking for a deeper exhaust note.
The more free flowing backbox allows for a sportier rumble and throaty sound on the throttle and also compliments the rear of the car nicely with sporty exhaust tips.
This system is 2.5 inches through with 2.75 inch exhaust tips.
The Verdict
As we touched on towards the beginning of this guide, what exhaust system you go for will depend on your goals and budget.
For maximum performance, consider an upgraded downpipe, sports cat and cat-back section. When going down this route, you may wish to opt for a resonated cat-back like the Scorpion system so it isn’t too loud. The downpipe and sports cat should be the priority for performance before the cat-back.
If it’s primarily sound you are after, you can’t go wrong with any of the Scorpion systems. If you’re on a tighter budget, then the Gravity system is also a good option.
Happy modding!
