Julian's '91 200 20vt

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themagellan
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Re: Julian's '91 200 20vt

Post by themagellan »

This thing is NUTS! Looks like a riot. So happy you got some videos - thanks for that.
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88a5tq
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Re: Julian's '91 200 20vt

Post by 88a5tq »

Haha I appreciate that but Chris, oh Chriss! Just had to bring up the micro-compressor's inability to get its sound up :wah:

It IS FUN though! !
1991 Audi 200q Holset
1991 Audi 200q Felbaum'd
1988 Audi 5000 TQ
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88a5tq
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Re: Julian's '91 200 20vt

Post by 88a5tq »

LOL I just noticed the cloud of dust everytime I lifter during LC. It's open to ATM pointing towards the trans so it cleans the concrete with the air

I bought that 54mm hx with a $70 credit. I'm gonna be swimming in turbos shortly
1991 Audi 200q Holset
1991 Audi 200q Felbaum'd
1988 Audi 5000 TQ
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88a5tq
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Re: Julian's '91 200 20vt

Post by 88a5tq »

Uh oh, it's a 6 pt nut. I don't want to get it balanced so I guess I'll be very diligent about marking all the assembly parts for alignment. Afterall, i did just order the rebuild kit. It's also dirt nasty. Hope I can clean it up easily.
IMG_14991.jpg
IMG_14991.jpg (104.84 KiB) Viewed 32232 times


I do find myself wondering if the supplied 12 pt nut in the rebuild kit has the same thread/pitch as the 6 pt and if I can change them but that seems risky considering balance and torque differences. Screw it I'll just reuse the nut
1991 Audi 200q Holset
1991 Audi 200q Felbaum'd
1988 Audi 5000 TQ
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loxxrider
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Re: Julian's '91 200 20vt

Post by loxxrider »

Is there something I should know about holsets with 6 pt nuts?
-Chris

'91 Audi 200 20v - Revver/BAT project
'91 Audi 200 20v Avant
'01 Anthracite M5
'90 M3
'85 Euro 635csi
'12 X3
E34 530i (maybe rear-mount soon)
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88a5tq
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Re: Julian's '91 200 20vt

Post by 88a5tq »

They are balanced as an assembly :D
Was your h1c a 6 pt?! Lol
1991 Audi 200q Holset
1991 Audi 200q Felbaum'd
1988 Audi 5000 TQ
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loxxrider
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Re: Julian's '91 200 20vt

Post by loxxrider »

I've never heard that. You sure? I think mine was 12 pt.
-Chris

'91 Audi 200 20v - Revver/BAT project
'91 Audi 200 20v Avant
'01 Anthracite M5
'90 M3
'85 Euro 635csi
'12 X3
E34 530i (maybe rear-mount soon)
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88a5tq
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Re: Julian's '91 200 20vt

Post by 88a5tq »

I have read it around on the diesel forums and other places but it could be garbage EXCEPT for the fact that the compressor wheel doesn't have balancing machining marks (chunks missing). I figure that means the compressor wheel isn't zero balanced :idunno:
1991 Audi 200q Holset
1991 Audi 200q Felbaum'd
1988 Audi 5000 TQ
Oldestof11
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Re: Julian's '91 200 20vt

Post by Oldestof11 »

Zach Faylor out of IA will rebuild and balance for a small fee.
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88a5tq
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Re: Julian's '91 200 20vt

Post by 88a5tq »

Lol no thanks I'll do it myself carefully again I think but I do have to say that I was unaware IA was even reachable under new ownership. I had no luck reaching them for a period of a month when I was calling and emailing. That was 2 plus yrs ago tho. Thanks for the info anyway :)

Have you heard the same or read the same concerning the nuts, eldest brother?
1991 Audi 200q Holset
1991 Audi 200q Felbaum'd
1988 Audi 5000 TQ
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loxxrider
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Re: Julian's '91 200 20vt

Post by loxxrider »

Man holsets can be so mysterious. Learn somethin new every day.
-Chris

'91 Audi 200 20v - Revver/BAT project
'91 Audi 200 20v Avant
'01 Anthracite M5
'90 M3
'85 Euro 635csi
'12 X3
E34 530i (maybe rear-mount soon)
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88a5tq
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Re: Julian's '91 200 20vt

Post by 88a5tq »

I'm not put off from the rebuild by the info since I took measures to rebalance through assembly even with the 12 pt. I'll likely rip this rebuild out WAY faster by comparison tho hah

Turbo felt a little slower but it was from my PID taking out too much DC yesterday after the 100% until factor dropped out. I've gotta give that a look tonight
1991 Audi 200q Holset
1991 Audi 200q Felbaum'd
1988 Audi 5000 TQ
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88a5tq
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Re: Julian's '91 200 20vt

Post by 88a5tq »

Things are looking good with car. New turbo is late in mail but that's old news. Running car at ~280 kPa but it was tapering off to 240 at 7k rpm due to PID growing pains. It's improving with tinkering. However, I don't feel that 11.5 degrees timing at 4k rpm and 280 kPa is enough :D I'll start messing with that. It does climb to 15 degrees by 8k iirc tho. Getting there
1991 Audi 200q Holset
1991 Audi 200q Felbaum'd
1988 Audi 5000 TQ
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loxxrider
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Re: Julian's '91 200 20vt

Post by loxxrider »

Don't get greedy...
-Chris

'91 Audi 200 20v - Revver/BAT project
'91 Audi 200 20v Avant
'01 Anthracite M5
'90 M3
'85 Euro 635csi
'12 X3
E34 530i (maybe rear-mount soon)
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88a5tq
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Re: Julian's '91 200 20vt

Post by 88a5tq »

That seems too much? Even for this little 50mm wheel? The meth injection may also have the "drowning" effect that it has sometimes when timing is left unchanged. I'm still learning so advice is welcome.

Also I forgot to mention that my oil cap isn't blowing oil anymore like it did before the holset went in. I guess maybe my CCV system may have been pulling too much direct vacuum on everything or something along those line :idunno:
1991 Audi 200q Holset
1991 Audi 200q Felbaum'd
1988 Audi 5000 TQ
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88a5tq
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Re: Julian's '91 200 20vt

Post by 88a5tq »

I'm still getting the PID dropping to 18is DC after coming within 40 kPa of target. I have raised P and lowered D as well as increase I to 50 but it still remains that it drops to 18 DC. Monkeying has not resulted in anything positive or positive reinforcement¿? I'll post the most recent pull, and holy shit did it pull HARD in first gear :D :D :D
1991 Audi 200q Holset
1991 Audi 200q Felbaum'd
1988 Audi 5000 TQ
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loxxrider
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Re: Julian's '91 200 20vt

Post by loxxrider »

88a5tq wrote:That seems too much? Even for this little 50mm wheel? The meth injection may also have the "drowning" effect that it has sometimes when timing is left unchanged. I'm still learning so advice is welcome.

Also I forgot to mention that my oil cap isn't blowing oil anymore like it did before the holset went in. I guess maybe my CCV system may have been pulling too much direct vacuum on everything or something along those line :idunno:


It's not about overall flow rate or power. It's about heat input and pressure (and power). A smaller compressor wheel flowing the same volume or mass flow rate as a larger one will always create hotter air. That's no good.


88a5tq wrote:I'm still getting the PID dropping to 18is DC after coming within 40 kPa of target. I have raised P and lowered D as well as increase I to 50 but it still remains that it drops to 18 DC. Monkeying has not resulted in anything positive or positive reinforcement¿? I'll post the most recent pull, and holy shit did it pull HARD in first gear :D :D :D


I don't understand. Can you try to explain that again? You aren't hitting your target?
-Chris

'91 Audi 200 20v - Revver/BAT project
'91 Audi 200 20v Avant
'01 Anthracite M5
'90 M3
'85 Euro 635csi
'12 X3
E34 530i (maybe rear-mount soon)
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chaloux
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Re: Julian's '91 200 20vt

Post by chaloux »

You want to tune your refdc table as much as possible in 3rd or 4th gear. Get it to produce the boost you desire at the RPM you desire it at (if possible) and then back the duty cycle off a bit. Then start with your PID tuning so that it can make up the last bit and does its job dealing with variables.

Maybe I'm wrong but I've always done it this way and always had very solid boost control.
Matt

18 Silverado 1500 work pig, roof rack and tonneau cover
11 Jetta sedan TDI DSG, rear muffler delete
GONE :( 87 4ktq - 4 FOX SNAKES

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88a5tq
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Re: Julian's '91 200 20vt

Post by 88a5tq »

The new control strategy has always been somewhat of a puzzle to me. Thanks for the help. I used the old way before because all the extra new PID settings seemed to be working against me. I suppose I could have the hz too low for the MAC also tho. I really don't want to give up on this valve.

It's always something between me and boost control hah
1991 Audi 200q Holset
1991 Audi 200q Felbaum'd
1988 Audi 5000 TQ
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88a5tq
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Re: Julian's '91 200 20vt

Post by 88a5tq »

Ya so it turns out I'm the idiot who adjusted his boost target to 280 kPa but neglected to change his rpm/ref DC table to reflect it. Hence the sudden drop to 10% towards redline :bangshead:
1991 Audi 200q Holset
1991 Audi 200q Felbaum'd
1988 Audi 5000 TQ
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88a5tq
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Re: Julian's '91 200 20vt

Post by 88a5tq »

I need some feedback on how much ignition retard is safe during launch control. I am only trying achieve fire ballz here! :D

Right now it's at 40°s but no fire throwing
1991 Audi 200q Holset
1991 Audi 200q Felbaum'd
1988 Audi 5000 TQ
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loxxrider
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Re: Julian's '91 200 20vt

Post by loxxrider »

I've gone to 50. You shouldn't need more. More boost and more fuel will make more fire usually. Sometimes it just doesn't seem to work though, like on Jim's 07k 4kq. I don't know why that thing never blew fire lol
-Chris

'91 Audi 200 20v - Revver/BAT project
'91 Audi 200 20v Avant
'01 Anthracite M5
'90 M3
'85 Euro 635csi
'12 X3
E34 530i (maybe rear-mount soon)
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88a5tq
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Joined: Wed Jul 16, 2014 10:27 pm

Re: Julian's '91 200 20vt

Post by 88a5tq »

Interesting. I was at 60 degrees as per efiexpress.com. also I turned off keep enrichment during ignition cut cuz it was just shooting black smoke while cutting. I wander if my empty cats might be killing the flames with their "resonator" chambers. I guess more fuel will be my next stop. I've also wandered if my meth injection could be acting against the flames as well.
1991 Audi 200q Holset
1991 Audi 200q Felbaum'd
1988 Audi 5000 TQ
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88a5tq
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Re: Julian's '91 200 20vt

Post by 88a5tq »

BTW, you all probably thought I'd forgotten about the 5k... BUT it's just been discussed and finalized that once the new holset is put in the 200 I'm gonna move on to a long term project of going Mad Max on the 5k. A lift kit is out of my budget but I'm going to put my welder to use and make a brush bar of sorts and change the paint to reflect it's new personality :D
1991 Audi 200q Holset
1991 Audi 200q Felbaum'd
1988 Audi 5000 TQ
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88a5tq
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Re: Julian's '91 200 20vt

Post by 88a5tq »

I've got a happy story here for yunz guys :D
Those guys at G&A don't even measure the inducer of these turbos before shipping them (apparently). I just eyeballed the new one with a ruler to the tune of ~2.1875 with a RULER. Sucker is 55.5mm bahahah! I got the monster hx35 on the 2nd shot. Pretty sweet.

However, this snail needs some serious love :(
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I suspected it was much bigger when my 54mm comp housing wouldn't fit it either. You know, the painted one they sent that I was hoping to use on this one. This should clean up good still I think.
1991 Audi 200q Holset
1991 Audi 200q Felbaum'd
1988 Audi 5000 TQ
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