Trying to remember this. If I recall boost is applied by the TCV allowing pressure to be sent to the wastegAte, which keeps it closed.
The 3.5 psi measurement is a calibration pressure applied to the wastegAte which is then set to the closed position following the procedure given in VIDA. Shortening -the rod will mean the wastegAte but opens later
Uh oh, what do I have wrong here ?
1996 855 T5 - Musings on Wastegate Adjustment
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Re: 1996 855 T5 - Musings on Wastegate Adjustment
Empty Nester
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hausmeister
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On the 850s the tcv opens the wastegate by applying pressure.
I recently played with my setup again. Relocated the tcv nearer to the turbo and shortened the hoses a lot. Since then i was able to increase the pretension again and also the boost build up is smoother since the tcv seems to be able to regulate better.
I recently played with my setup again. Relocated the tcv nearer to the turbo and shortened the hoses a lot. Since then i was able to increase the pretension again and also the boost build up is smoother since the tcv seems to be able to regulate better.
850 T5-R '95 auto 

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Reviving old topic
Here is the picture of my discontent
Yet people report enhanced Or earlier boosting when shortening the wastegate rod.

Here is the picture of my discontent
Yet people report enhanced Or earlier boosting when shortening the wastegate rod.
Empty Nester
A Captain in a Sea of Estrogen
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Link to Maintenance record thread
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hausmeister
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that should explain it
850 T5-R '95 auto 

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Ha!!
Dumba$$ moment.
Im watching this thinking I know all this already - then realize my mistake - really simple one.
WASTEGATE CLOSED = maximum boost
WASTEGATE OPEN = no boost.
So, as the spring and diaphragm age, the Wastegate Adjuster has less tension to close the waste gate, and it stays open and reduces boost. Shortening the rod compensates for the weakness and closes the waste gate like new.

Dumba$$ moment.
Im watching this thinking I know all this already - then realize my mistake - really simple one.
WASTEGATE CLOSED = maximum boost
WASTEGATE OPEN = no boost.
So, as the spring and diaphragm age, the Wastegate Adjuster has less tension to close the waste gate, and it stays open and reduces boost. Shortening the rod compensates for the weakness and closes the waste gate like new.
Empty Nester
A Captain in a Sea of Estrogen
1999-V70-T5M56 2005-V70-M56 1999-S70 VW T4 XC90-in-Red
Link to Maintenance record thread
A Captain in a Sea of Estrogen
1999-V70-T5M56 2005-V70-M56 1999-S70 VW T4 XC90-in-Red
Link to Maintenance record thread
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Awarded this 9 April in the year of our Swede 2018
Empty Nester
A Captain in a Sea of Estrogen
1999-V70-T5M56 2005-V70-M56 1999-S70 VW T4 XC90-in-Red
Link to Maintenance record thread
A Captain in a Sea of Estrogen
1999-V70-T5M56 2005-V70-M56 1999-S70 VW T4 XC90-in-Red
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It could have been worse... You could be the broke guy that makes sure everyone on government assistance gets their benefits - on time even. 
Wisdom requires knowledge as a prerequisite, but knowledge can be developed due to a lack of wisdom.
In order to learn how to fix something, you must first learn how to break it.
1999 V70 XC AWD 2.4 T -- ~231k miles
1998 V70 2.4 NA -- ~184k miles
In order to learn how to fix something, you must first learn how to break it.
1999 V70 XC AWD 2.4 T -- ~231k miles
1998 V70 2.4 NA -- ~184k miles
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