Well, it's finally time to finish up the power modifications to the GTi. I dropped off the car with Dion at
Drive Auto Works (DAW) shortly after Thanksgiving so they could get to work on it while I was away on business. First up is an upgrade to the IS38 turbo used in the Golf R / Audi S3 to get a better power curve. It's just a slightly bigger turbo than the stock IS20 so it makes similar peak torque numbers but doesn't drop off in power as you get up into the higher rpms which is really where the difference counts. I had them transfer over the CTS Turbo inlet and muffler delete but this time I decided to keep the stock diverter valve rather than install an aftermarket one. My understanding is that it really shouldn't be needed for this revision of the IS38 and the aftermarket ones can cause more issues than they help.
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| New IS38 Revision F Turbo |
Since they were going to have to disconnect the CTS downpipe to install the new turbo, I wanted to replace it altogether with a new one from AWE. The AWE downpipe has the advantage of having a flex pipe built into the design to allow for movement and minimize the chance of cracking under stress. More importantly, it has a German high quality HJS cat on it so I know it'll perform optimally.
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| AWE Downpipe |
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| Delicious HJS Cat |
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| IS38 and AWE Downpipe installed - 12/4/2019 |
Of course, if we're going through the trouble of installing a new turbo and downpipe, I might as well upgrade the intercooler as well. DAW hooked me up with pricing on a Wagner intercooler which should provide much-needed cooling of the boosted air come summer. It's a nice OEM like fit but is thicker and higher quality with no plastic pieces.
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| Wagner Intercooler - 12/6/2019 |
With power almost double, and the car having over 50K miles already, I figured an upgrade to the engine and transmission mounts would be in order. Since this is a daily I didn't want too much NVH so I went with 034 Motorsports Density Line of mounts. These are still rubber but are solid and have a slightly harder rubber than factory. It keeps the engine in place without adding annoying NVH to the cabin and they're an excellent street upgrade mount set.
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| 034 motorsports density line engine and transmission mounts - 12/6/2019 |
Finally, all this hardware isn't going to do much without a tune. I already put in one step cooler plugs and new coils
a few weeks ago so she was all ready to get the APR Stage 3 IS38 high torque tune. It now makes around 350 hp and 350 ft-lb of torque to the wheels which I think is actually pretty absurd for a FWD car but it'll sure be fun and is now officially the most powerful car in the Steguis Motorsports fleet which I find a bit hilarious. The car drives phenomenally well. It has a very OEM driving feel and pulls really hard all the way to the top. It feels like a proper hot hatch now.
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| APR IS38 Stage 3 High Torque Tune - 12/6/2019 |
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| APR Stage 2 high torque for reference |
Big thanks to Dion at DAW for getting me all sorted and Rad at
Tatis Motorsports for helping me source some of the parts so I could get this done when I wanted this past week. Now that we're all done with power mods, I just a few more cosmetic tweaks to make and she'll be exactly where I want her to be and I can close out this build.
