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The 5 Best Performance Mods for the MK5 GTI
Volkswagen’s 5th gen GTI was first produced in 2004 and ran until late 2008. If you’ve read many of our posts, you would know that this is the model that really got me into Volkswagen’s. This GTI was actually named 2007 Automobile of the Year by Automobile Magazine. The MK5 GTI’s featured a 2.0t FSI engine that put down 197hp and 207lb-ft torque, which is pretty good out of the factory. This engine features two different transmissions: a 6-speed manual and a 6 speed DSG automatic transmission.
Ignition Coils & Spark Plugs
Before we get started with this mod guide, let’s talk a second to talk about ignition coils and spark plugs. We highly recommend changing all of your spark plugs and all of your ignition coils to ensure you get the full sense of performance out of your engine and mods. As crazy as it sounds, if there is one bad plug or coil, it could cause the engine to not run at optimal levels. This could make you feel that you wasted your money on mods, when in fact it’s just one bad ignition coil or spark plug. With that said, before ordering any of the mods below get some fresh plugs and coils.
If you are tuned or plan on getting tuned, we highly advise going with the 1-step colder spark plugs. The more boost you’re running, the hotter the engine gets, which leads to misfires under full throttle on OEM spark plugs. PFR8S8EG – (heat-range code 8). Especially if you happen to have a K04 upgrade, you will want to go with 1-step colder. Spark plug gapping can vary from .024, .026, or .03 depending on the engine.
Buy Here: 1-Step Colder MK5 GTI Spark Plugs
How to Make Your Golf Mk5 GTI Faster – MK5 GTI Mods
To make your Volkswagen MK5 GTI tuned machine, you will need to add these aftermarket MK5 GTI mods:
- ECU Tune
Aside from the downpipe, there are basic bolt-on mods that should be able to be DIY projects. We’ll get into the brands that we like the most, but want to mention, this is OUR opinion and there are so many other brands out there that provide similar aftermarket parts. Before purchasing any mod, please make sure to do your own research as well to get the mod that will fit your wants and needs.
1. MK5 GTI Aftermarket ECU Tune
A tune will almost always be the biggest bang for your buck when it comes to performance mods. The tune that comes out of the factory has much more conservative settings because not everybody buys a GTI to be aggressive believe it or not. Engine performance is one of the many reasons why we suggest a tune, but certainly not the only reason. So what are the other reasons:
- More performance
- Helps make your vehicle more efficient
- Easy install
- Provides a cleaner burn
- Fits your driving needs
There are many aftermarket companies out there that provide great products, but these are the ones we are liking.
APR is a well-known U.S. aftermarket company that is known for its R&D. Their tunes pack a punch, but aren’t entirely plug and play. You will have to use certified APR Dealers for installation, however. This may seem unfortunate, but it will be worth it in the end. APR’s tunes go all the way to Stage 3.
Stage 1 Power Gains 91 Octane: +42hp & +59lb-tq
Stage 1 Power Gains 93 Octane: +50hp & 74lb-tq
Price: $359.96 + Free Shipping (Suggested Retail)
Unitronic is another common German aftermarket manufacturer. Their products for the MK5 are very common in the space. Something cool about Unitronic is UniCONNECT+ which allows you to program your own vehicle right in your own garage. Unitronic’s tunes also go up to Stage 3 with the proper parts.
Stage 1 Power Gains: +45hp & +68lb-tq
Price: $550 + Free Shipping (Suggested Retail)
2. Aftermarket Downpipes
An aftermarket downpipe, often referred to as DP, is an important part to upgrade if you are going for real power. It connects the turbo to the exhaust system. To ensure the MK5 GTI’s are compliant with emissions, they come standard with two catalytic converters. As you can imagine, these restrict airflow quite a bit and produces a high amount of backpressure. A combination of backpressure and restricted airflow dampens the engine’s performance. Without a tune, a downpipe can increase hp by 5-20, but WITH a tune, your MK5 GTI could gain up to 80 hp.
Something worth mentioning is that some people don’t care to spend the money on quality downpipes and will just use a metal pipe. Don’t do it.. Just stick with tried and true downpipes that have been researched and tested by big aftermarket brands.
Raceland may not be a very popular German aftermarket manufacturer, but they do make a very common downpipe for Volkswagen’s. The downpipe will bolt directly to the OEM turbo and is 3″ in diameter. This downpipe incorporates bungs for OEM sensors to retain proper engine management. Although this is one of the cheaper options on the market, it is a great route if you’re trying to get your money’s worth.
Unitronic makes it on the list again because, as stated above, they make great products for Volkswagen’s. This DP has a 200-cell high flow catalytic converter if you’re in a state that has strong emissions laws. It is a direct fit onto the OEM turbo and is 3″ in diameter. It is a little more expensive than the Raceland, but mainly due to the catalytic converters.
Price: $599.00 (High-Flow Catalytic Converter)
3. Aftermarket Intercoolers
A mod that never gains a lot of attention is intercoolers. Yes, it may not be a purely performance mod, but it is an efficiency and reliability mod that allows a lot more power compared to the stock unit. An intercooler brings in air to the combustion chamber and the colder that air is, the more power you will see, hence going with an aftermarket intercooler. Cooler and denser air will produce more power to the engine. Now they run more on the expensive side when it comes to aftermarket mods, but again if you are going for real power, these are a necessity.
The main reason aftermarket intercoolers are named efficiency mods is that they reduce the engine killer “heat soak”. The longer you run your vehicle, the more likelihood heat soak will set in and take power “out of your engine”. An aftermarket intercooler runs much cooler than a stock unit and ensures optimal temperature levels all while the engine is running.
APR is on the list again and for good reason. Their intercoolers get a great rep for their R&D efforts and releasing that research to the end consumers. This unit features a bar and plate core that is 40% bigger than the OEM unit. It is on the expensive side, but if you end up going this route, you won’t regret it.
4. Aftermarket Intakes
Now, these last 2 mods are always argued as a waste of money, but we’ll dive into them now and give our opinions. Air intakes should not be bought strictly for power output. However, compared to OEM intakes, aftermarket intakes bring in a lot more air. The more air the engine pulls in; the more power the engine kicks out. Some other benefits of air intakes:
- Increased airflow
- Less pressure drop
- “Whoosh” noise
- Engine bay aesthetic
BSH intakes may not be a common aftermarket brand, but they do provide high-quality products. Its one-piece intake design fits directly in the stock engine without any added parts. Their True Seal Airbox utilizes factory ram air ducting for more increased airflow. The price tag is very reasonable compared to many others on the market.
Power: 10-15hp (as advertised) More like 3-5 if tuned
Neuspeed is probably one of the more common aftermarket manufacturers of Volkswagen parts. This P-Flo kit boasts impressive flow bench results of 529 CFM @ 23″ of water compared to the OEM airbox the produces 346 CFM @ 23″ of water. It is a direct fit for the 2.0t FSI engine. Something cool about this unit is you can choose an oil or dry finish and a red or black finish.
Power: 10-15hp (as advertised) More like 3-5 if tuned
5. Aftermarket Exhaust
Like the intake, an aftermarket exhaust doesn’t provide much power gains, but it will provide an aggressive sound that we all strive for. Sound aside, an aftermarket exhaust does reduce backpressure because typically the diameter is a little bigger and less restrictive. There are a lot of aftermarket exhausts to choose from on the market, but we’ll limit it down to two that we like the most.
Eurojet Racing is a very common and reputable aftermarket company that makes parts specifically for Audi’s and Volkswagen’s. This exhaust features a direct fit with 2.5″ in diameter, which produces more torque. The reason we like this exhaust is that there isn’t much drone, it’s not overly loud, quieter in lower RPMs, but it’s aggressive enough to make heads turn.
Conclusion – MK5 GTI Mods
We want to mention, that the brands and products we have listed above are OUR favorites, but please make sure to do your research as well because everybody has different preferences. Make sure the parts above fit your MK5 GTI, especially because there is a TFSI and TSI engine. We hope this guide has helped you in your research. Let us know what mods you have on your MK5 GTI!
Read up more on MK5 GTI Common Problems!