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IS20 Instalation Guide (1.8t)

toledospeed

Go Kart Champion
Location
3rd rock
Cool, looks good! It actually shows the coolant hose I broke in one of the pics you used. I'll provide an annotated pic when I get a chance, along with the part number and some advice to make folks aware so they can avoid my mistake. The guy with the GTI appears to have broken the same hose in the video, but he doesn't go into any detail about how it happened.

In the first picture, in the yellow rectangle, it shows the coolant hose (left arrow) that attaches to the plastic vent valve (right arrow) that comes out of the cylinder head. The vent is just a plastic adapter with an o-ring gasket that seals it into a hole in the cylinder head above the built-in exhaust manifold. There are not any moving parts as the term "valve" might suggest. On top, there is a plastic tube fitting that sticks straight up to allow the attachment of the hose. The aperture at the top of the fitting is not much larger than a pin hole. It simply allows trapped air to vent into the coolant hardline and back to the coolant overflow reservoir.

06K-121-143, Vent Valve, $3.36
06K-121-051-M, By-Pass Hose, $6.80
https://www.vwpartsvortex.com/oem-parts/volkswagen-vent-valve-06k121143

Before removing the turbo, I would suggest removing the hose from the plastic vent fitting so it doesn't stick up as in the first picture. Be careful messing with the vent and it's hose fitting, it is very cheap plastic and will easily break. If you leave the hose intact like I did, just be very aware that it is there and don't knock the turbo into the hose.

In the second pic, it shows how the plastic hose fitting sheared off the vent valve when I hit the hose with the IS12 turbo assembly when pulling it out. It was very easy to do since there is a lot going on when you pull the turbo out. An extra pair of eyes watching all the different things you are trying not to damage may have prevented this. For a temporary fix, I was able to plug the hose going into the hardline and also plug the vent valve with a plastic pin and some blue permatex gasket maker. This allowed me to finish the job until the $3.36 part arrived.

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4MotionWagen

Ready to race!
Location
Michigan
Another one down! IS20 and USP catted downpipe are now installed! Thanks again MeltedSolid for this awesome guide. I used the exact same method, except for minor details here and there. I haven't opened her up past half throttle yet as I have just been driving around getting the coolant settled and making sure I don't have any leaks. So far, so good! Now I have to get the JB4 dialed in to see how that works. A tune is going to be tempting to get better fueling if I hit the ceiling sooner than I would like.

Are you stacking with a tune? If not will this run on stock mapping until you dial in the JB4? If so, anything to watch out for on stock mapping until it is dialed in like not going full throttle until dialed in?

I have a GSW 4motion with JB4 and an IS20 sitting in my office that i bought before I bought the car for just this reason. lol
 

toledospeed

Go Kart Champion
Location
3rd rock
Are you stacking with a tune? If not will this run on stock mapping until you dial in the JB4? If so, anything to watch out for on stock mapping until it is dialed in like not going full throttle until dialed in?

I have a GSW 4motion with JB4 and an IS20 sitting in my office that i bought before I bought the car for just this reason. lol

No, I am on JB4 only. Still running conservative map 6 (16 psi) and not doing too much with it until I know for sure all is well, but will be turning it up a bit more here soon! I've gotten on it a few times and it put a big grin on my face, lol. Stock mapping should be fine, ecu will request psi to reach requested load. You won't see much if any performance benefit on stock map.
 

MeltedSolid

Autocross Newbie
Location
San Francisco Bay Area
Car(s)
'15 Golf, e36 328i
Are you stacking with a tune? If not will this run on stock mapping until you dial in the JB4? If so, anything to watch out for on stock mapping until it is dialed in like not going full throttle until dialed in?

I have a GSW 4motion with JB4 and an IS20 sitting in my office that i bought before I bought the car for just this reason. lol

The gist I'm getting from swapping turbos on our engines is that the only downside of not properly tuning for it is you won't see the performance gains so it's pointless. It seems to completely safe other than if you request too much boost too early, which would cause compressor surging, but that won't happen on a stock map and the JB4 can't compensate for that yet anyways.
 

4MotionWagen

Ready to race!
Location
Michigan
No, I am on JB4 only. Still running conservative map 6 (16 psi) and not doing too much with it until I know for sure all is well, but will be turning it up a bit more here soon! I've gotten on it a few times and it put a big grin on my face, lol. Stock mapping should be fine, ecu will request psi to reach requested load. You won't see much if any performance benefit on stock map.


The gist I'm getting from swapping turbos on our engines is that the only downside of not properly tuning for it is you won't see the performance gains so it's pointless. It seems to completely safe other than if you request too much boost too early, which would cause compressor surging, but that won't happen on a stock map and the JB4 can't compensate for that yet anyways.

Thank you for the replies. I do have a JB4 and do plan on using it. I just didn't want to put the IS20 on and be forced to do a bunch of tuning before I could drive it as it is my DD. Also if I need to take it to the dealer for unrelated warranty work or for an ECU update or a recall where they wouldn't notice the turbo but would notice the JB4 and needed to take the JB4 off to get the work done. I think it just might happen on my next vacation.
 

toledospeed

Go Kart Champion
Location
3rd rock
Does the IS12 DV work on the IS20?

Yes, they are interchangeable between IS12 and IS20. My IS20 had one with less miles, so I kept that one.
 

MeltedSolid

Autocross Newbie
Location
San Francisco Bay Area
Car(s)
'15 Golf, e36 328i

toledospeed

Go Kart Champion
Location
3rd rock
Just an update on my install. All is good after two weeks. I just returned from a 600 mile round trip and all went well. Averaged 35-36 mpg for both legs of the trip, so I didn't lose anything in the fuel economy department. That is as good if not better than it ever did before with my driving style. I checked the oil and coolant levels last night and they are still right where they started. Great! Now it is time to start the JB4 tweaking to see what she can do. I am currently running a modest 16 PSI peak on map 6 and it already feels much stronger up top than the 17.5 PSI map 6 I was running before the swap. Hopefully the JB4 updated firmware comes out soon so I can work with the latest revision.

Still getting used to the extra noise of the new DP. Sometimes it seems quieter than others, so it is likely just certain RPM and conditions. At 65-80 mph cruising on the highway, it is very close to stock and there isn't any drone with my custom MF cat-back with resonator. However, there is a little drone (extra sound to some!) at certain RPM's during normal acceleration. It is kind of growing on me though. I love how it sounds in the parking garage at work, LOL.
 

TwinDad

Autocross Newbie
Location
Fort Lee, NJ
Just an update on my install. All is good after two weeks. I just returned from a 600 mile round trip and all went well. Averaged 35-36 mpg for both legs of the trip, so I didn't lose anything in the fuel economy department. That is as good if not better than it ever did before with my driving style. I checked the oil and coolant levels last night and they are still right where they started. Great! Now it is time to start the JB4 tweaking to see what she can do. I am currently running a modest 16 PSI peak on map 6 and it already feels much stronger up top than the 17.5 PSI map 6 I was running before the swap. Hopefully the JB4 updated firmware comes out soon so I can work with the latest revision.

Still getting used to the extra noise of the new DP. Sometimes it seems quieter than others, so it is likely just certain RPM and conditions. At 65-80 mph cruising on the highway, it is very close to stock and there isn't any drone with my custom MF cat-back with resonator. However, there is a little drone (extra sound to some!) at certain RPM's during normal acceleration. It is kind of growing on me though. I love how it sounds in the parking garage at work, LOL.

Crank that thing up!! Lol. You should be able to easily set it to 20+ at 4,000-4,500 and then taper it down to 18 at 6,500.
 

Ton

Go Kart Newbie
Location
U.S.
Yeah. The larger IS20 changes the sound dynamics more than you would expect. I like a quiet car, so it took my a little to get used to it. Its not loud, just more noise stock and it comes right from the downpipe area.
 

MikeF1021

Ready to race!
Location
MA
About to pull trigger on a dp for when I throw my is20 in... ill definitely be sure to include a good resonator to keep drone down... any recommendations for resonators?

Have most of you kept your 1.8 exhaust stock with this mod? I was considering a muffler delete but not now that I'm getting a downpipe...

I figure the increased volume and throatiness from the is20 and larger downpipe will be enough for me... a little attitude is fine but I want to keep my daily somewhat civil.
 

TwinDad

Autocross Newbie
Location
Fort Lee, NJ
About to pull trigger on a dp for when I throw my is20 in... ill definitely be sure to include a good resonator to keep drone down... any recommendations for resonators?

Have most of you kept your 1.8 exhaust stock with this mod? I was considering a muffler delete but not now that I'm getting a downpipe...

I figure the increased volume and throatiness from the is20 and larger downpipe will be enough for me... a little attitude is fine but I want to keep my daily somewhat civil.

Get a catted downpipe and leave the stock exhaust. Our mufflers are a lot quieter than the gti. Wrap the top section of the downpipe as well. This will help Kee it quieter a bit. Stock intake still? That will make a difference in sound as well. For quiet, stealth operation, leave it stock, remove the snow grate, cut out the grill vents and use a drop in filter. I think it will have a nice sound with out being too loud
 

toledospeed

Go Kart Champion
Location
3rd rock
Crank that thing up!! Lol. You should be able to easily set it to 20+ at 4,000-4,500 and then taper it down to 18 at 6,500.

Hahaha! Don't worry, she is going higher soon! I am now running 17 PSI as of this morning and will see how that goes. I like be methodical and ratchet things up slowly so I don't put any undo stress on the motor. Unfortunately, we have had a lot of rain in our area, so this has limited the time I can do testing. That said, I am not sure we will have the fueling capacity to do the 20 PSI and up without E85 mix or a flash tune, at least from what I have seen thus far. I really would like a 93 octane only tune, but I am not against trying the E85 mix. Just not convenient to run all the time though.

Yeah. The larger IS20 changes the sound dynamics more than you would expect. I like a quiet car, so it took my a little to get used to it. Its not loud, just more noise stock and it comes right from the downpipe area.

I never had the DP before with the IS12, so I wasn't sure what it was that would have even been like. I guess I went from stage 1 to stage 3, so to speak. There is more noise the DP area for sure. At first I thought I may have a small leak somewhere around there, but after running some tests, that definitely isn't the case.

About to pull trigger on a dp for when I throw my is20 in... ill definitely be sure to include a good resonator to keep drone down... any recommendations for resonators?

Have most of you kept your 1.8 exhaust stock with this mod? I was considering a muffler delete but not now that I'm getting a downpipe...

I figure the increased volume and throatiness from the is20 and larger downpipe will be enough for me... a little attitude is fine but I want to keep my daily somewhat civil.

I have a custom cat-back with a Jones JR-25 resonator and a MF straight-though muffler. It was tame with the stock DP. Some would say it was too tame, but it gave the car a bit more growl and I knew I would be doing a DP at some point. I would not do the muffler delete with the DP unless you like it LOUD, LOL. If you want to tame the DP, I would go with a resonator on the DP, just like on the stock DP. I still may do this, or I may swap out my Jones resonator for a large vibrant resonator. That said, I am getting used to things as they are and the sound is actually pretty good. Like you said, there is just a little attitude there. There are a few RPM ranges where it drones a bit, but I am rarely in those zones when doing normal driving. I'll document this a bit more and report back once I get it figured out.

Get a catted downpipe and leave the stock exhaust. Our mufflers are a lot quieter than the gti. Wrap the top section of the downpipe as well. This will help Kee it quieter a bit. Stock intake still? That will make a difference in sound as well. For quiet, stealth operation, leave it stock, remove the snow grate, cut out the grill vents and use a drop in filter. I think it will have a nice sound with out being too loud

Hmm, I may try wrapping the top section of the DP and see how it goes. Seems like I should be able to get to it even while it is on the car. I wonder how hard, if possible, will it be to remove the wrap later on?
 

Ton

Go Kart Newbie
Location
U.S.
Get a catted downpipe and leave the stock exhaust. Our mufflers are a lot quieter than the gti. Wrap the top section of the downpipe as well. This will help Kee it quieter a bit. Stock intake still? That will make a difference in sound as well. For quiet, stealth operation, leave it stock, remove the snow grate, cut out the grill vents and use a drop in filter. I think it will have a nice sound with out being too loud

Do you think the 2.25 exhaust becomes a bottleneck with the is20?
 
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