Want to Modify your GTI? Start Here


Automotive Engineer
I decided to make a thread to help give direction to our newcomers. Most of which have never experienced VW like some have with the 1.8T or the FSI/TSI engine base. Hopefully, after you're done reading you will have enough resources and tools to figure out where you need to go, who you need to ask, and ultiamtely what you want out of your vehicle

I'll try to take a very Unbiased approach and at least hit on the general topics while trying not to be vague. We all know there are many companies out there that over the same products. Ultimately you will have to do the research yourself to figure out who you want to use for all of your aftermarket needs. Some people cross market, some people stick to one tuner. Its all about preference and LUCKILY there are enough reputable tuners out there that provide good products

Where Do I Start?

Well thats a good question. Let's lay out some general points:

1) Browse around the forums for a little while: Take in some of the lingo and seek out personnel that might be of help and could answer your questions in the future. Jot down notes that you might find interesting and just relax and have fun. Mostly, we're very welcoming and enjoy random discussions

2) Learn to search: Our search function blows.....we all know that. Might I suggest using the google site tag function and do your searching through there (

3) If you want to start a thread, make sure it hasnt been discussed already. If you're too scared too, Private message someone who you think could answer your question. Normally, people will steer you in the right direction.

4) Once you've gathered some knowledge and intel, Establish a plan for your vehicle: This plan does not need to have an ending, but figure out if you want to stay stock, or go further into the rabbit hole. Trust me, if you're on here long enough you WILL be spending money.

5) Enjoy the time with your vehicle at first. Normally, your car is broken in from the factory since its purpose built. But take that 1000miles to really think it over about where you want to go with it. Track Monster? Backroad Buner? Low and Slow? Show Stopper? Its your car! Do with it what you please.

"Break In Period"

1) Your car is purpose Built
2) 99% Of the break in is done from the factory
3) You're not going to hurt your car
4) Read:

What Modifications are out there?

This section will be long! Sit back and take some notes

Drivetrain Performance:

  • ECU Tuning: Refer to this thread - || Gains within tuning are normally any where from 50bhp with Stage 1 and 70bhp with Stage 2 tuning. This is all purely based on your stock levels though.
  • Turboback Exhaust / Catback Exhaust (TBE/CBE): || A downpipe is required for Stage 2. Make sure you research your how loud you want it, and the quality of what you're willing to spend for. Most of the time, you get what you pay for. That statement holds pretty well with a few outliers that will try and trump some statistical data. Also, research your emission laws in your state. Can you even go stage 2? That will help make your decision. This point in the process is where you need to become more dependent on researching your own information. If you have emission laws, it has been discussed MANY times before.
  • Mounts: Good thread to check out: || Mounts will help put more power down by eliminating the loss within the rubber deflection in your current stock mounts. It will also help with Wheel hop. I suggest researching this HARD.
  • Water/Meth: || For the users who want great cooling + Octane boosting. Water meth allows you to run 93OCT pump gas while running a 100OCT file in your tuning.
  • Turbo Outlet Pipe (TOP): || Replaces the stock pancake pipe for roughly 4-5HP gains Brands Include: AWE / BSH / Neuspeed
  • Noise Pipe and Soundaktor Delete: Eliminates the sound makers on your vehicle to enjoy a REAL engine sound
  • Intercooler (IC): Stage 2 starts to teeter on the edge of heat soaking. Depending on climate and local, start pricing your options. One of the BIGGEST reasons to eliminate heat soak is for consistency during driving or WOT pulls. Heat soak will eliminate any sort of power and make your car feel like a pig. Some Brands Include: APR / Audi S3 / EuroJet / Forge / Godspeed / VF / etc.
  • Intake: This topic has bee long discussed and beaten to a pulp. PLEASE Research intakes before you post asking questions. Intakes added with tuning produce some pretty nice gains. Brands Include: APR / VWR / AWE / BSH / Neuspeed / K&N / Forge / ITG / Modshack / List goes on.....
  • Clutches: Clutch failures are common amongst 6Speed owners when modifying, however, its too random to pinpoint whether its a manufacturer problem or a modification problem. However, the clutch WILL slip going higher into the modification path. Research thoroughly.
  • DSG TCU Tunes: As for the DSG owners, there are tunes out there that helps with driveability. Normally, the DSG has been rated up to 550AWHP, and there are many users with Stage 3 levels running stock clutch packs with no issues whatsoever.
  • Diverter Valve (DV): Stock Revision G valves are a diaphragm design that is pron eto ripping under increased boost conditions and sometimes, stock conditions. Upgrade to the Revision D valve or Revision C (Piston Type).
  • OEM Driver Gear Springs or VWR: Modest Drop. Linear Spring Rates. Excellent ride quality.
  • Spring/Shock Combo: These setups are widely used across the platform. Normally the price is right and they can offer great performance. However, some people complain about harsher ride quality and more bounciness over bumps. Purely subjective, but you must ultimately decide. Some Brands include: Koni / Eibach / Tein / Neuspeed / Bilstein / H&R
  • Coilovers: HUGE HUGE HUGE Topic that has been covered extensively. There are many many brands to choose from and even different driving styles and ride qualities you must sift through to make your decision. THIS is a topic you will need to ask the experts on to determine your end goal. Brands Include: Koni / ST / KW / K-sport / FK / Raceland / Saachs / HPS / Bilstein / H&R / List goes on....
  • Air Bags: || Good place to start and go from there
  • Bushings: Bushings are much like the mounts. They will help soldify the driveline and help put more power down. Some Brands inclulde: Whiteline (W.A.L.K) / OEM Audi S3 and TT / Energy Suspension /
  • Sway Bars: Geat for Roll Stiffness. There are many threads out there to sift through, but a google search will ultimately help you decide which brand to run and which diameter to run. Some people are happy with a rear bar and others are happy with both front and rear. Brands Include: APR / H&R / Hotchkis / VWR / ECS / Eibach / BSH / etc.
  • Chassis Braces: || Great modification to remove chassis twist/flex. Some Brands Include: Stern / Ultra Racing / Unibrace
  • Tires: || Tires are what connect you to the ground. So ultimately, they are one of the most important parts of your driveline. What's 300+HP good for if you cant put it to the ground? There are many options out there in regards to summer tires, but consider using tirerack to make your choices.
  • Subframe Collars: and || Look at it like a FRONT Chassis brace. It'll help take up the slop from your subframe and actually provide a better steering feel through the corners. Also, your alignment will be much more even from side to side.

  • OEM
    • Lines: Stainless Steel Brake Lines help with brake fade due to excessive use and flexibility in the stsock lines. Brands: USP / Neuspeed
    • Pads: We all know what brake pads are......Brands to Consider: Hawk / Stoptech / EBC / Carbotech /
    • Fluid: Commonly used Brands to Conisder: ATE / Motul
    • Bushings: Tyrol has a brake stiffening kit that provides even wear on the pads and rotor:
  • OEM+
    • Golf R/R32/Passat BBK: Single piston and heavy, but a good choice to look at. These offer roughly %25 increase in stopping power.
    • Porsche 4Pot BBK: A flashier upgrade than the R32 brakes. They are Brembo 4 piston calipers that are lighter and provide better clamping force to the STOCK 312mm rotor.
  • Other Name Brand BBKs
    • Brands Include: Stoptech / Wilwood / ECS / Forge / Brembo / Racing Brake / VWR

- While we might consider wheels an aesthetic modification, you can greatly drop some unsprung weight when upgrading. This in turn will give you less rolling weight which in turn uses less power to turn the wheel.
- Some affects of lightweight wheels vs. heavier wheels are traction differences and reluctance of slowing down or speeding up, but normally lightweight wheels will offer a nimble ride with better performance.
- More on this later

This is purely up to you. The way the car looks should be determined by the end user, but some gems include:
  • LED R-Tails
  • Front Lip Spoiler
  • Tint
  • Xenons

  • Boost Gauge: Definitely need this for any turbo charged vehicle. It help diagnose as well as let's you see how your car is performing. gets you street cred :) Common Brands to Consider: AWE / NewSouth / CIM / Podi / P3 Digital /
    • Boost Tap: You will need this to have a boost gauge. It taps into the intake manifold to grab the actual manifold pressure: Common Brands to Consider: APR / AWE / NewSouth / 42DD / BSH / Forge
  • VAGCOM: If youre looking to understand and diagnose your car further, VAGCOM is the key to do it. Not only can you recode certain convenience items (Window up/down with Key Fob, etc), you can log different parameters of your car and send them to various companies for them to troubleshoot. No worrying if the tuner is miles away! More Information here:
  • Preventative maintanence: Keep up with your maintanence program. I'd highly suggest if you choose to modify your engine to switch your oil changes to every 5K miles. is a great place for OEM parts at an affordable sales price for all of maintanence needs.

Recommended Build Plans

Obviously this plan is not for everyone and everything can be changed at a moments notice, but it can help give you an idea of a typical path one wouold take in modifying their GTI.

Stage 0
- Summer Tires
- REV D (or Piston C) Valve
- CBE (Or stock for that added sleeper sound)
- Brake Pads/Lines/Fluid
- Short Shifter (If that's your thing)
- Suspension

Stage 1
- Stage 0 Modifications
- Stage 1 ECU Tune
- Intake
- VagCom
- Boost Gauge
- Possibly S3 Intercooler if stopping here

Stage 2
- Stage 1 Modifications
- Downpipe
- Stage 2 Tuning (Downpipe required)
- CBE if that floats your boat
- Engine/Trans/Dogbone Mounts
- Intercooler. Size dependent on your local
- Around this stage, you're going to need a stiffer suspension to hold some power
- Bushings

K04 (or Stage 2+)
- Stage 2 modifications
- K04 Compressor
- Intercooler is a must
- Clutch Upgrade
- Suspension to match for traction

Stage 3
- Stage 2 Modifcations
- GT28/GT30 Turbo and Tuning
- W/M
- Clutch Upgrade
- GREAT Tires
- Suspension to match for traction

- At this point, you should know what you need to do :D
- Injectors
- Rods
- Pistons
- Etc.........

Mods vs. Warranty

Read this:–Moss_Warranty_Act

Then understand: Unless the modification is the direct root cause of your problem, they cannot void your warranty. However, they still can refuse service and not work on your vehicle.

In a nutshell.....that's about it. Hopefully that will give you an idea where to start and at least some direction to go search it out. Always feel free to ask questions!
Last edited:


Drag Race Newbie
mods, pls sticky.


Go Kart Champion
epic win grambles.:thumbsup:


Automotive Engineer
HAHAHA... those must be some large nuts!! HAHAHA...

lol How big do you like your nuts? I figured the newcomers can munch on those for a little while and give them just a little bit of direction.



Go Kart Champion
Thread stickied :thumbsup:


Automotive Engineer
thank you. wish there was a way that new members would have to read and acknowledge this thread.

Like a link they click in the registry to activate their account. That would awesome.


Go Kart Champion
Good thread :)

Now we can point the n00bs here after they make their first posts!


Automotive Engineer


Go Kart Champion
Should lock it too. Don't need to clutter this thread up.


Ready to race!
great work!


Go Kart Champion
K04 is Stage 2+? APR classifies it under Stage 3.

Also, add something in about warranty. Something such as, "Your warranty may or may not be honored by VW or your dealer if you modify your car.

TLDR; Don't modify your car if you can't afford to repair and maintain it without the factory warranty."


Ready to race!
Good thread :)

Now we can point the n00bs here after they make their first posts!

Until they lurk and learn to start with "well I read that stickied post but it didn't answer my question so can I go stage 2 without a down pipe?"