Best First Mods (2021 GTI S)

[ImpetuousOne]

Bingo, cap the existing intercooler. There's a few tutorials out there as well! When I get mine ordered and start I’ll be sure to video it and put it up

Safe to assume at least some of those manufacturers include caps for the oem IC?

 

[Buck43]

Safe to assume at least some of those manufacturers include caps for the oem IC?

Mostly no... in fact I don’t believe any do, however a vinyl cap should do the trick.

https://www.usplastic.com/catalog/i...MIrt3O4bj77wIVof_jBx0ueA4FEAQYAiABEgITaPD_BwE

 

[ImpetuousOne]

Mostly no... in fact I don’t believe any do, however a vinyl cap should do the trick.

https://www.usplastic.com/catalog/i...MIrt3O4bj77wIVof_jBx0ueA4FEAQYAiABEgITaPD_BwE

Thinking about it more, my last 2 aftermarket ICs for my FiST and EcoStang came with caps, so...
Time's running short before we're back in the furnace

 

[launchd]

So you’re saying that the only difference between some companies’ stage 1 and 2 tunes is turning off the o2 sensor? But they have power gains too how does that work?

I guess I just meant more that the downpipe wouldn’t really be doing much without a tune like in mind a downpipe is a power mod while a catback is just the sound. That’s my goal rn is just sound mainly

You're correct, a downpipe will not be adding much (performance wise) without software (stage 2 tune) that is accounting for it.

I'm not sure what companies @It's Sam is talking about but I can confirm APR's stage 2 software isn't just a way to eliminate the P0420 cat efficiency CEL. In fact, some companies offer stage 2 tune variants that do not do anything to the rear O2 sensor reading or code out the CEL...

APR stage 2 test pipe file disables/codes out the rear O2 sensor (prevents/masks P0420 cat efficiency CEL)
APR stage 2 non test pipe file does not disable/code out the rear O2 sensor (does not prevent/mask P0420 cat efficiency CEL)

O2 spacers absolutely work but will require some trial and error. The specific component of a downpipe that makes this a trial and error process is the cat. Not all cats are created equal and, cats are wear and tear components that degrade (perform worse) over time. If you have no cat and/or a low-grade/worn out cat and you try to eliminate an efficiency CEL (that isn't being eliminated by the tune) with an O2 spacer, you will likely fail or have a very hard time doing so.

To pass most state's emissions, you can't run a tune that is preventing/coding out the CEL, you will fail due to readiness issues. This is why you read people stating "Stage 2 tunes won't pass emissions, you need to revert to stock/stage 1 and/or reinstall the stock downpipe" all the time. However, with a stage 2 tune that isn't preventing/coding out the CEL (APR stage 2 non test pipe file, as an example), a downpipe with a cat that isn't garbage/worn out and an O2 spacer, you can pass. Unless of course you live in a state that does a visual inspection too as part of the emissions process... then you're fucked and have to revert back to the stock downpipe.

I pass NYS inspection/emissions with my APR downpipe, APR stage 2 tune (non test pipe file) and an O2 spacer (Vibrant J - smallest fitting). All my monitors are in a "Ready" state and this is how I drive my car everyday, no CEL. I've been running this setup since June 2020 (almost a year with no CEL). I did have my O2 spacer removed a few months back to see what would happen and, within the first 60 miles of driving, P0420 cat efficiency CEL. Cleared codes/put it back, no CEL since/all monitors ready. I will pass emissions when I go to have it done in June, running a downpipe, running a stage 2 tune, with an O2 spacer in place, unless my cat becomes too degraded.

I have 44,000 miles on my APR downpipe for further reference*

 

[shovelhd]

The very first thing I would do is upgrade your tires, and wheels if you want. Your new tires aren't getting any newer and are worth money towards the upgrade. The gold standard street tire is the Michelin Pilot Supersport but there are plenty of other good ones as well. I run General GMax. At the same time, I would upgrade the dogbone insert as the additional traction will stress the stock insert. I have BFI Stage 1 but they are hard to get. I agree with the Powerflex.

The next thing I would do is a rear sway bar. I have an ST Suspensions but there are plenty of good 24/25mm bars to choose from.

Now that your car will handle getting the stock power down, I'd look at engine upgrades. I'd do the intercooler first, especially since you live in Arizona. This will help even with a stock tune. Where you go from there is up to your budget. JB4, tune, downpipe, exhaust, depends on your budget. Be very careful mixing exhaust upgrades. You could end up with a foul smelling, cabin shaking, fart sounding excuse for a GTI. The stories here are legendary. Do your homework. Don't take the easy way out by just asking for opinions.

Good luck and welcome.

 

[AzTRgti]

You're correct, a downpipe will not be adding much (performance wise) without software (stage 2 tune) that is accounting for it.

I'm not sure what companies @It's Sam is talking about but I can confirm APR's stage 2 software isn't just a way to eliminate the P0420 cat efficiency CEL. In fact, some companies offer stage 2 tune variants that do not do anything to the rear O2 sensor reading or code out the CEL...

APR stage 2 test pipe file disables/codes out the rear O2 sensor (prevents/masks P0420 cat efficiency CEL)
APR stage 2 non test pipe file does not disable/code out the rear O2 sensor (does not prevent/mask P0420 cat efficiency CEL)

O2 spacers absolutely work but will require some trial and error. The specific component of a downpipe that makes this a trial and error process is the cat. Not all cats are created equal and, cats are wear and tear components that degrade (perform worse) over time. If you have no cat and/or a low-grade/worn out cat and you try to eliminate an efficiency CEL (that isn't being eliminated by the tune) with an O2 spacer, you will likely fail or have a very hard time doing so.

To pass most state's emissions, you can't run a tune that is preventing/coding out the CEL, you will fail due to readiness issues. This is why you read people stating "Stage 2 tunes won't pass emissions, you need to revert to stock/stage 1 and/or reinstall the stock downpipe" all the time. However, with a stage 2 tune that isn't preventing/coding out the CEL (APR stage 2 non test pipe file, as an example), a downpipe with a cat that isn't garbage/worn out and an O2 spacer, you can pass. Unless of course you live in a state that does a visual inspection too as part of the emissions process... then you're fucked and have to revert back to the stock downpipe.

I pass NYS inspection/emissions with my APR downpipe, APR stage 2 tune (non test pipe file) and an O2 spacer (Vibrant J - smallest fitting). All my monitors are in a "Ready" state and this is how I drive my car everyday, no CEL. I've been running this setup since June 2020 (almost a year with no CEL). I did have my O2 spacer removed a few months back to see what would happen and, within the first 60 miles of driving, P0420 cat efficiency CEL. Cleared codes/put it back, no CEL since/all monitors ready. I will pass emissions when I go to have it done in June, running a downpipe, running a stage 2 tune, with an O2 spacer in place, unless my cat becomes too degraded.

I have 44,000 miles on my APR downpipe for further reference*

That’s kind of what I figured. I planned to do more handling mods before trying to go stage 2/dp route. Tbh I may just be happy with a nice stage 1 tune as this cars already the fastest I’ve ever owned and I think a small bump in power would make it just about perfect

The very first thing I would do is upgrade your tires, and wheels if you want. Your new tires aren't getting any newer and are worth money towards the upgrade. The gold standard street tire is the Michelin Pilot Supersport but there are plenty of other good ones as well. I run General GMax. At the same time, I would upgrade the dogbone insert as the additional traction will stress the stock insert. I have BFI Stage 1 but they are hard to get. I agree with the Powerflex.

The next thing I would do is a rear sway bar. I have an ST Suspensions but there are plenty of good 24/25mm bars to choose from.

Now that your car will handle getting the stock power down, I'd look at engine upgrades. I'd do the intercooler first, especially since you live in Arizona. This will help even with a stock tune. Where you go from there is up to your budget. JB4, tune, downpipe, exhaust, depends on your budget. Be very careful mixing exhaust upgrades. You could end up with a foul smelling, cabin shaking, fart sounding excuse for a GTI. The stories here are legendary. Do your homework. Don't take the easy way out by just asking for opinions.

Good luck and welcome.

So you’re suggesting to sell my tires while they’re still almost brand new to help fund the Pilot’s? That’s not a bad idea tbh I didn’t think of it. Didn’t really think used tires were worth much but you’re right I can probably get a good amount for em if I sell em soon. I might keep them for the possible snowboard trips I take during the winter though.

Okay so which powerflex insert do I go with?? The one that was linked earlier (https://www.powerflexusa.com/shop/p...ower-engine-mount-hybrid-bushing-large-b-2437) looks to be more than just the insert and I noticed there’s different versions. I think I would need version B am I correct?

 

[Acadia18]

Throw her on jack stands, pop the bumper, couple of hose clamps pop off and cap the stock intercooler, install FMIC with a couple brackets and bolts and pop bumper back on.

That doesn't sound like a nice way to tread your wife...

 

[PenIsland]

I’m not one of those forum snobs that get upset when the thread derails. I intended to have this thread be all encompassing anyways so yhis the kind of info I’m looking for! So you’re saying that the only difference between some companies’ stage 1 and 2 tunes is turning off the o2 sensor? But they have power gains too how does that work?

I guess I just meant more that the downpipe wouldn’t really be doing much without a tune like in mind a downpipe is a power mod while a catback is just the sound. That’s my goal rn is just sound mainly



that’s great to hear! I think I’m ordering it tonight

Try to find the AWE exhaust used. Personally, I can't justify paying full price for it when you can find some used ones in great condition with all the hardware for almost half the price.

I got mine of Facebook marketplace for $400 in mint condition

 

[shovelhd]

That’s kind of what I figured. I planned to do more handling mods before trying to go stage 2/dp route. Tbh I may just be happy with a nice stage 1 tune as this cars already the fastest I’ve ever owned and I think a small bump in power would make it just about perfect

So you’re suggesting to sell my tires while they’re still almost brand new to help fund the Pilot’s? That’s not a bad idea tbh I didn’t think of it. Didn’t really think used tires were worth much but you’re right I can probably get a good amount for em if I sell em soon. I might keep them for the possible snowboard trips I take during the winter though.

Okay so which powerflex insert do I go with?? The one that was linked earlier (https://www.powerflexusa.com/shop/p...ower-engine-mount-hybrid-bushing-large-b-2437) looks to be more than just the insert and I noticed there’s different versions. I think I would need version B am I correct?

Yes. You should be able to get between $200-$300 for the set. Buy the new stuff first, ASAP. If your trips to the mountains are infrequent, just rent a Rav4. I live in snow country so I'm on real winter tires 5 months out of the year. I spray bombed my factory wheels and mounted a used set of Blizzaks. That seems like an unnecessary investment.

Not sure which Powerflex, ask them or search on the forum.

 

[AzTRgti]

Powerflex hybrid dogbone insert is the move and I would go with Raceseng over BFI any day of the week for shifters.

One word of caution, be careful when choosing your exhaust as a loud one with the stock downpipe will become VERY loud with an aftermarket one. Good luck and welcome to the forums.

Would you recommend the hybrid over just the plain insert? From my research the hybrid would require me to cut out the bottom bushing...how hard is that? I’m leaning towards just the insert at this point for ease of install but if the hybrid isn’t that hard to install I read that it has more benefit for manuals than just the insert

 

[El_bigote_AJ]

Would you recommend the hybrid over just the plain insert? From my research the hybrid would require me to cut out the bottom bushing...how hard is that? I’m leaning towards just the insert at this point for ease of install but if the hybrid isn’t that hard to install I read that it has more benefit for manuals than just the insert

I went from the metal insert to the poly insert to the hybrid Version now... hybrid is hands down my favorite.

Cutting it is not hard at all, the factory bushing has a plastic ring as the main body of the bushing with the rubbing Inside it creating the outward pressure that keeps it captive in the subframe, all you have to do it get a little jigsaw or body saw blade inside the gap of the bushing and then cut the plastic ring to break the tension that’s keeping it captive then it just pulls right out. The plastic is not thick at all either maybe 2mm thick

 

[PowerDemon]

Would you recommend the hybrid over just the plain insert? From my research the hybrid would require me to cut out the bottom bushing...how hard is that? I’m leaning towards just the insert at this point for ease of install but if the hybrid isn’t that hard to install I read that it has more benefit for manuals than just the insert

I’m a big fan of the hybrid. Based on everything I’ve read it performs better than just the insert but I don’t have any personal experience so you’ll have to be the judge of that.

I thought the install was simple. You just need to take a little saw blade (I used a jig saw blade) and cut out the old one which isn’t too difficult if you have a jack and some jack stands. You just cut a little notch in it, grab it with a pair of pliers, and pull it out. Then you lube up the new insert and just push it in. Torque to spec and you’re done.

There is some good information throughout this thread if you’re in for a read. I also talked a little about the install in my build thread here https://www.golfmk7.com/forums/index.php?threads/powerdemon’s-15-mk7.372686/.

Edit: I cannot get my build thread to hyperlink for the life of me.

 

[AzTRgti]

I went from the metal insert to the poly insert to the hybrid Version now... hybrid is hands down my favorite.

Cutting it is not hard at all, the factory bushing has a plastic ring as the main body of the bushing with the rubbing Inside it creating the outward pressure that keeps it captive in the subframe, all you have to do it get a little jigsaw or body saw blade inside the gap of the bushing and then cut the plastic ring to break the tension that’s keeping it captive then it just pulls right out. The plastic is not thick at all either maybe 2mm thick

I think I’m leaning towards the insert for now. Which one am I going to need with my ‘21? Version B correct? https://www.powerflexusa.com/shop/p...t-lower-engine-mount-insert-large-type-b-2436

 

[Striker23]

So if I’m understanding this video correctly the diesel geek is all installed on the transmission side not under the knob? That’s cool as hell most short shifters I’ve seen were under the actual shift handle. I can definitely handle this in my garage haha

I didn’t install mine but my mechanic had no issues. It’s adjustable so you can play around with it. you can have short throws and then another adjustment tightens them up even farther. Mine is on the normal setting. I have none of the issues getting it into gear that I had before. Love the mod! You won’t be disappointed

 

[AzTRgti]

I didn’t install mine but my mechanic had no issues. It’s adjustable so you can play around with it. you can have short throws and then another adjustment tightens them up even farther. Mine is on the normal setting. I have none of the issues getting it into gear that I had before. Love the mod! You won’t be disappointed

I’m super excited about it. One of my biggest complaints with this car is the shifting action and from what I’m reading this seems to be exactly what I’m looking for. This with the weighted knob (when it comes in) will make a world of difference.

Planning on doing the CDV delete as well while I have the air box off. Should have the exhaust this weekend so by end of the month this car will be a totally different beast!

Debating on pulling the trigger on the powerflex insert I linked above tonight or tomorrow. Might as well do that when I install the exhaust