Where to stop?

Fix_Until_Broke

Top Post Dawg
Joined
Aug 8, 2004
Location
Menomonee Falls, Wisconsin, USA
TDI
03 Jetta, 03 TT TDI
After the exhaust was all fixed, next was the oil drain line for the 2nd turbo. This was also very tedious and time consuming. First I made a template with wire, then I made a first example out of 1/2" brake line (cheap) and then made the final one out of stainless.

None of the bends are in line with each other, a little error on one makes the end off by a mile, but it fit the first time.











As you can see in the below pictures, it's a cozy fit





The tube just terminates about an inch below the clamp in the below picture. The hose is just pushed up over the tube and then just has a 90 degree -8 AN fitting that connects to the pan.





After this, it's really just cleaning up all the little details and the rest is just re-assembly like any other car. I put my O2 sensor in the downpipe.

 

Fix_Until_Broke

Top Post Dawg
Joined
Aug 8, 2004
Location
Menomonee Falls, Wisconsin, USA
TDI
03 Jetta, 03 TT TDI
Finally have a crank case vent that is not just a hose out the bottom of the car. Wye'd in a tube off the turbo inlet pipe.







There's a bunch more little details that I didn't get pictures of. You can tell I took less and less pictures as the project went on :). From the Friday before Christmas to the Sunday after New Years I put over 100 hours in. That was from the engine/trans hanging from the 4 bolts in the car to driving it. I was surprised how many little details there were to do and figure out.

Here's everything in and running - Looks more/less stock doesn't it ;)





It still needs to be tuned, it runs pretty well on 4 different ECU's from 3 different tuners, though it goes into limp mode if boost is too high for too long. It'll run a solid 30 psi split pretty evenly between the two turbos (15 psi each). The wastegate settings I had were pretty close to start with. Smoke is pretty much non existent, AFR's run in the low 20's, EGT's in the 1100's max. No fuel has been added with any of the tunes so no significant power changes yet.

Low end transient response didn't change at all - no difference in driveability - in fact, you wouldn't know the 2nd turbo is there in normal driving.

I think I'm in a corner already for using the GTC1444VZ for significant compounding. The compressor side does not seem to be much of a limitation, however the exhaust side still requires a lot of differential pressure to build high boost which drives EMP's really high really quick. Take any exhaust away from it and it falls on it's face quickly. Not sure if I'll need to run a compressor bypass or not, but am pretty sure I'll need to let the HE221 do most of the work at higher RPM's to avoid the EMP's going crazy high.

I'm sure I forgot to mention a lot of things, but that's most of it I think. Feedback, comments, questions, suggestions are always welcomed!
 

GOFAST

Well-known member
Joined
Oct 1, 2014
Location
nederland
TDI
vento afn
nice work.

looks stock indeed.
turbo oil return looks like a work of art.
when does the car go to a dyno ?
love to see the result and some IMP vs EMP data.
 

Fix_Until_Broke

Top Post Dawg
Joined
Aug 8, 2004
Location
Menomonee Falls, Wisconsin, USA
TDI
03 Jetta, 03 TT TDI
Dyno is built into the car - see this thread for more details.

I need to get my full kit of DAQ more permanently mounted in the car so I can go out and do a run without having to set everything up each time. More work to do with the cylinder pressure measurement, establishing TDC and crank position on the fly as well as being able to log ECU driven parameters.

Hopefully once I get all the above setup and a process established to quickly/easily interpret all this data, I can work with a tuner or start modifying maps myself.

Currently the HE221 runs right about 1.1:1 IMP:EMP and the GTC1444 runs anywhere from 1:1 to 2.5:1 depending on load and RPM as previously documented here.. They appear to be straight additive.
 

hatemi

Veteran Member
Joined
Aug 25, 2005
Location
Finland
TDI
Audi A6 4F 3.0TDI
Good work fitting those turbos in a tight space. I know it's tedious work since I'm building a compound set for my BMW. 2060vklr and S362SX-E.
 

nicklockard

Torque Dorque
Joined
Aug 15, 2004
Location
Arizona
TDI
SOLD 2010 Touareg Tdi w/factory Tow PCKG
Not sure if I'll need to run a compressor bypass or not, but am pretty sure I'll need to let the HE221 do most of the work at higher RPM's to avoid the EMP's going crazy high.

I'm sure I forgot to mention a lot of things, but that's most of it I think. Feedback, comments, questions, suggestions are always welcomed!
Sweet setup. That's how the 335D does it--compressor bypass just routes all air to the low pressure, high volume turbo at higher rpm's and requested airflows to avoid choking the flow by the little compressor. And on the exhaust side, there is a continuously variable turbine bypass valve (proportional). I think it pretty much bypasses the small turbine 100% once the small compressor is bypassed.

Normal flow at low rpm's is for all exhaust gases to exert on [(edit: this is wrong inside brackets)big turbine first, then little turbine in series (big one passes enough pressure downline to spin the little one up fast enough; and big compressor feeding the little one air.] Exhaust pressure is like hatemi says: pushes on small first then big, like this:




All the magic happens in the tuning relationships between the proportional valve doing its thing and when the compressor bypass does its thing.

Edit to add: FWIW, you could add a purely mechanical spring-operated check valve (butterfly or swing valve) for a compressor bypass at higher pressures and not have to add electronic controllers/actuators.
 
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hatemi

Veteran Member
Joined
Aug 25, 2005
Location
Finland
TDI
Audi A6 4F 3.0TDI
On x35d exhaust goes to the small turbo first and then gets bypassed to larger one. I'm using LCI 535d manifold on my build and the bypass gate is located on the same port as it is originally.
 

[486]

Top Post Dawg
Joined
Mar 1, 2014
Location
MN
TDI
02 golf ALH
All compound setups are small turbine closer to the engine, going the other way would be... improper for all sorts of reasons.

compressor bypass is often unnecessary as well, at least with interstage charge cooling but also maybe it is just fine without, even with little gt14 compressor it still flows quite a bit compared to these little engines. You will find more "airflow" gain in better charge distribution from a different intake than anything at this point.
 

Fix_Until_Broke

Top Post Dawg
Joined
Aug 8, 2004
Location
Menomonee Falls, Wisconsin, USA
TDI
03 Jetta, 03 TT TDI
All the magic happens in the tuning relationships between the proportional valve doing its thing and when the compressor bypass does its thing.

Edit to add: FWIW, you could add a purely mechanical spring-operated check valve (butterfly or swing valve) for a compressor bypass at higher pressures and not have to add electronic controllers/actuators.
You mean like this ;)?





This came in today as well :)



Hatemi - That's a nice looking setup you have there.
 

turbovan+tdi

Top Post Dawg
Joined
Mar 23, 2014
Location
Abbotsford, BC.
TDI
2003 TDI 2.0L ALH, auto, silver wagon, lowered, Colt stage 2 cam, ported head,205 injectors, 1756 turbo, Malone 2.0, 3" exhaust, 18" BBS RC GLI rims. 2004 blue GSW TDI, 5 speed, lowered, GLI BBS wheels painted black, Malone stage 2, Aerotur
Not much to add except stock intake, bah, lol. :eek:

Very nicely done, I just can't find the motivation to do anything like this anymore. Mad props. :cool:
 

[486]

Top Post Dawg
Joined
Mar 1, 2014
Location
MN
TDI
02 golf ALH
Still have stock SMIC as well that's holding on at 35 psi still.
heh, mine was the same for a while on my old compound setup. Never blew the tanks off like people said it would, in fact the plastic pancake pipe never even had the spring clip hose connector come apart.
It's still on the car actually as the interstage CC, seeing like 20 PSI? I forget, car's been apart for too long.
 

FRtdilover

Well-known member
Joined
Nov 4, 2015
Location
europe
TDI
2001 4motion ARL 150
Awesome thread ! lot of work has been done here!
Looking forward to see the final result (hp, torque, driveability etc)
 

Fix_Until_Broke

Top Post Dawg
Joined
Aug 8, 2004
Location
Menomonee Falls, Wisconsin, USA
TDI
03 Jetta, 03 TT TDI
FRtdilover - thanks for the kind words.

I cleaned up a few misc things this weekend. Pulled a trailer with it and it worked pretty well.

Had a coolant leak on a hose up by the brake booster - simple fix (cut an inch off the hose) but took 2 hours to get to it and get it fixed due to all the stuff in the way.

Figured out that I forgot to plug the two extra ports on the bottom of the wastegate so had a boost leak off the high pressure turbo (oops!). Plugged those holes.

Fixed my clutch line clip - more on that in another thread.

My oil pan looks like it's leaking where I TIG welded it for the main bolt clearance :(. Will have to pull that off sometime and fix that.

Have a bit of oil dripping out of the low pressure compressor outlet - Will need to pull that off and will likely make a new piece using this adapter from Eurotrash. This will be aluminum instead of stainless which will be a bit lighter as well.

Not sure where the oil is coming from - Hopefully it's the CCV that's now connected in and not turbo seals on the HE221W.

Got the 6 Bar MAP sensor wired in/hooked up - took it for a test drive and then promptly took it back out - not driveable without tune updates, but it's ready to go when that happens.

Tried a couple different wastegate configurations between the high and low pressure turbo compressors on top/bottom of the wastegate just to see how it behaves now that I've got the one side of the diaphragm sealed up. Wish I could see/know when the wastegate was opening somehow.

All in all, it's coming together - next big step will be software updates.
 

turbovan+tdi

Top Post Dawg
Joined
Mar 23, 2014
Location
Abbotsford, BC.
TDI
2003 TDI 2.0L ALH, auto, silver wagon, lowered, Colt stage 2 cam, ported head,205 injectors, 1756 turbo, Malone 2.0, 3" exhaust, 18" BBS RC GLI rims. 2004 blue GSW TDI, 5 speed, lowered, GLI BBS wheels painted black, Malone stage 2, Aerotur
Very cool. How much boost? What do you think you are making, power wise?
 

Fix_Until_Broke

Top Post Dawg
Joined
Aug 8, 2004
Location
Menomonee Falls, Wisconsin, USA
TDI
03 Jetta, 03 TT TDI
It's not really tuned at all - still running ECU's that were tuned for a 17/22. Really just learning what does what mechanically before trying to get the software updated. Can't fix hardware with software :).

It'll run ~40 psi over 3000 RPM with the current setup.
VNT actuator vacuum is zero after it's spooled up
HE221W runs 20-25 psi boost and 30-35 psi exhaust pressure
GTC1444VZ runs at 40-45 psi boost and 50-60 psi exhaust pressure
Except for the initial spool up, the boost is entirely mechanically controlled. This isn't necessarily by design, just how it is right now.

I have not put any of my DAQ on and that will be the next step, to gather some data, before tuning it much farther. As I mentioned before, my goal is a very driveable/responsive 200 HP and as much torque as 200 bar PCP's will allow - hoping for 400 ft-lbf and near instant throttle response.

I will say, that for the relatively small amount of "tuning" I've done, it runs well - no compromises thus far - transient response is just as good as before, top end is significantly improved - runs like the GTB2260VKLR in the TT over 3000 RPM instead of getting choked out. All without adding any fuel.
 

GOFAST

Well-known member
Joined
Oct 1, 2014
Location
nederland
TDI
vento afn
good question. :D
love to see a film


It's not really tuned at all - still running ECU's that were tuned for a 17/22. Really just learning what does what mechanically before trying to get the software updated. Can't fix hardware with software.
indeed that's what I what to do as well when the time is there.
first make the hardware as good as it gets.
than mod the software........the probably fine tune the hardware again.
 
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Fix_Until_Broke

Top Post Dawg
Joined
Aug 8, 2004
Location
Menomonee Falls, Wisconsin, USA
TDI
03 Jetta, 03 TT TDI
I'll see if I can get a video of it sometime, maybe this weekend. It really does not sound any different than it did before - not louder or quieter really on the exhaust side.

There is a very faint whistle at idle on the compressor inlet that's kind of nice, but nothing really different under boost or anything.
 

FRtdilover

Well-known member
Joined
Nov 4, 2015
Location
europe
TDI
2001 4motion ARL 150
A lot of people are running single turbo, for a 250/300hp goal the bit of lag it has could be reasonable for some people, not for some other who don't want to feel any lag. Compound turbo is a good experiment, we can use parallele twin turbo, biturbo with bypass, without, ... just need to do the research, calculations, welding and building job by yourself, but that's worth it.
A friend of mine is building an AGR with a sequential biturbo setup and I like to compare the differences between the two builts, for example he will use a kkk03 as small wastegate turbo and a gtb2276vklr as the big turbo, with an exhaust bypass + an other one that will shunt the small turbo compressor housing in high rpm. It's not built yet unfortunatly but I'll collect some info to see how it will respond and the differences between the two biturbo builts.
 
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Fix_Until_Broke

Top Post Dawg
Joined
Aug 8, 2004
Location
Menomonee Falls, Wisconsin, USA
TDI
03 Jetta, 03 TT TDI
Been running well for the last ~6 months or so. Probably have ~10k miles on it, maybe 1k pulling a trailer which it does well. Last couple highway trips returned 51 MPG which was nice.

I put a 4 Bar MAP in a while ago and that has worked out very well. I pulled the skid plate off tonight to make an actuator adjustment and found this...



Oops - that's one of the two bolts that hold exhaust "bucket" to the engine. Looks like a fatigue failure. The other is still hanging on and the plumbing will support it to some degree as well, but I'll need to get it fixed.



I've also received the compressor outlet adapter from eurotrash so I have that to put in and re-do the LP compressor outlet plumbing.

I'd like to determine if I have a rear main seal leaking or if the TIG welded oil pan is leaking and ultimately fix the oil leak

I'd like to remove the NLS throwout bearing spacer as the clutch engagement is really high.

I also have a Darkside FMIC to install and would like to find a PD150 intake manifold to use as well.

Might be just as easy to pull the engine & transmission again when doing all these things at one time.
 

Fix_Until_Broke

Top Post Dawg
Joined
Aug 8, 2004
Location
Menomonee Falls, Wisconsin, USA
TDI
03 Jetta, 03 TT TDI
So, I've been playing around with this compound setup a bit and have come to the conclusion that the LP turbo exhaust housing is too small. I'll try to get a video of my gauges to justify this claim, but when I only have 10-15 psi differential pressure across the GTC1444VZ exhaust side and 40+ psi differential across the HE221W exhaust side, we've got a problem :). I bet this turbo would be relatively acceptable as a single!

Since most of this will come out anyway to do the list of work above, I should probably consider a different LP turbo or at least different exhaust side on this turbo. It spools much earlier than I would have expected so making the cold side a little bigger wouldn't hurt my feelings either. Though if it stayed the same and I was able to knock off 10-15 psi on the exhaust side would be a significant improvement as well.

Is there a larger exhaust housing/wheel for the HE221W available? I'll be re-doing the compressor outlet plumbing so a little fab work is not a big deal to put a whole different turbo in. Maybe an HX30W? I need to do some more research, but hoping for some educated guesses from the peanut gallery :).
 

[486]

Top Post Dawg
Joined
Mar 1, 2014
Location
MN
TDI
02 golf ALH
Is there a larger exhaust housing/wheel for the HE221W available?
iirc the wheel itself was larger than TD04HL, but that may be just faulty memory of mine. Your housing should be 5 or 6 cm volute, they make up to 8.5cm for the TD04 IIRC.
I'm running a 7cm, but don't have an interstage EGP gauge yet.
 

1.4TDI PD

Well-known member
Joined
Jul 12, 2017
Location
slovenia
TDI
2.5TDI V6, 3.3TDI V8,3.0TDI V6,1.9TDI PD100
Nice build love to watch the progress of the project keep up the work.
 

andy2

Veteran Member
Joined
Sep 24, 2004
Location
Bowmanville,Ontario,Canada
TDI
13 Jetta,94 Golf drag car 585bhp,Samurai buggy BHW 300bhp,97 Ram cummins
How are you controlling the high pressure bypass wastegate ?

It might be helpful with a setup like yours to measure the high pressure turbo's shaft speed.Using the pressure ratio's to setup a compound/staged setup does seem to work ok however the shaft speed would be best when using a HP VNT with HP bypass I'm guessing.

My old double VNT compound setup had a 62mm high pressure turbine exducer and a 64mm low pressure turbine exducer.It worked very well.

Point being that as long as the LP drive pressure is equal to or lower than the HP drive pressure then its acceptable as long as pressure ratios and/or shaft speeds are acceptable.

I'm running the gt2052w with a 40mm inducer hx30w (6cm a/r 52mm turbine exducer).I have a 46mm inducer hx30w coming with the same 6cm a/r 52mm turbine exducer to try out.
 

Fix_Until_Broke

Top Post Dawg
Joined
Aug 8, 2004
Location
Menomonee Falls, Wisconsin, USA
TDI
03 Jetta, 03 TT TDI
[EDIT] - See post 514 and disregard most of what's in this post [/EDIT]

I was able to take a couple video's today. Not great, but should be sufficient to get the point across.

I need to go find the specs/measurements on the HE221W

The high pressure bypass wastegate is currently spring only - both sides of the diaphragm are vented to atmosphere. I believe it opens at ~50 psi differential and I'm also reasonably confident that it does not open at all. There is also a wastegate on the HE221W that is set relatively high (at least 30 psi) and I'm also pretty confident that it's not opening either. So basically I have a VNT high pressure turbo and a fixed low pressure turbo plumbed in a straight series compound configuration.

Left Rear - Air Fuel Ratio

Left Front - Green needle - GTC1444VZ Boost Pressure
Left Front - Red needle - GTC1444VZ Exhaust Pressure

Middle Rear - VNT Vacuum to GTC1444VZ

Right Front - Green needle - HE221W Boost Pressure
Right Front - Red needle - HE221W Exhaust Pressure (+2.5 psi offset = 1 division) [EDIT] This gauge is FUBAR - Conclusions are inaccurate [/EDIT]

https://youtu.be/DBarFEhI7sM

https://youtu.be/DBarFEhI7sM

I'll add some screen shots and thoughts tomorrow after I get some time to review them.
 
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andy2

Veteran Member
Joined
Sep 24, 2004
Location
Bowmanville,Ontario,Canada
TDI
13 Jetta,94 Golf drag car 585bhp,Samurai buggy BHW 300bhp,97 Ram cummins
Its not too bad when considering that this is a VNT with a fixed geometry turbo.

I would be more inclined to upsizing the compressor on the LP turbo without upsizing the turbine very much if any at all.

The problem with upsizing the LP turbine too much bigger is that it will stress out the HP turbo before the LP comes alive.Not only that but you lose the transient response and the quick building pressure that makes compounds fun.

It looks like the hp turbo is pulling pretty hard against the LP before it comes alive according to the video.

I still highly favor the double vnt setup for a daily driver.A gtb2260vk might be a killer HP turbo for you IMO.Just plumb both actuators in parallel.
 

Fix_Until_Broke

Top Post Dawg
Joined
Aug 8, 2004
Location
Menomonee Falls, Wisconsin, USA
TDI
03 Jetta, 03 TT TDI
andy2 - thanks for your opinion. I was focused on reducing the LP exhaust back pressure, but you're suggesting to increase the LP boost pressure instead which hand't even crossed my mind.

I agree that the HP compressor is "pulling" on the LP compressor on spool up, else I have a sticky gauge. I think I might have a compound gauge somewhere (-30inHg to 30 psi) that I'll try and connect to the LP compressor outlet and confirm this. When the LP turbo went on, there was not a noticeable change in transient response.

I have a GTB2260VK as a single on the TT and I don't think it would be a good HP turbo for what I want to do unless there's a lot of help from the LP turbo on the initial spool up. It will make 15+ psi boost at 1800 RPM, but you'll wait 2-3 seconds to get it.

Thanks again for the ideas - I'll sleep on them :)
 
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