How to adjust VNT stop screw ?

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How to adjust VNT stop screw ?
#1
As above 

Read online should wind it out until 2-5 psi is seen at 2000rpm without any load. 

Is this correct / best way to do this. 


Needs to be done as i have replaced the chra. 

Turbo is a gt2052V on a 1.9 XUD
Cherry red 205 XUD VNT - Project thread here http://306oc.co.uk/forum/showthread.php?tid=25522
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#2
ordinarily id say leave it along, but as you've replaced chra not much good to you

have you got an emp gauge? thats what id be watching to adjust for spool

err on the side of caution, and adjust in small increments
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#3
No emp or egt gauges yet will be getting some and this can wait until iv got them .

So maybe start with 2 PSI at 2k rpm with no load to be cautious

Thanks
Cherry red 205 XUD VNT - Project thread here http://306oc.co.uk/forum/showthread.php?tid=25522
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#4
No load, mine doesnt boost tbh.
Wishes for more power...
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#5
(27-09-2015, 09:20 PM)Piggy Wrote: No load, mine doesnt boost tbh.

Are you sure ? I can remember even on a T2 if I revved the engine you'd see the boost gauge move a little bit.
Also a GT2052S will do about 5psi on a xud when reved with no load.

Have ordered EGT and EMP Gauges, will report back once I have these on.
Cherry red 205 XUD VNT - Project thread here http://306oc.co.uk/forum/showthread.php?tid=25522
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#6
Get your EMP gauge on, will be easy to find a happy medium then. 2:1 EMP to Boost Ratio is what I roughly worked on, seemed to hold together and still does to this day.
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#7
(28-09-2015, 09:43 AM)andyyy Wrote:
(27-09-2015, 09:20 PM)Piggy Wrote: No load, mine doesnt boost tbh.

Are you sure ? I can remember even on a T2 if I revved the engine you'd see the boost gauge move a little bit.
Also a GT2052S will do about 5psi on a xud when reved with no load.

Have ordered EGT and EMP Gauges, will report back once I have these on.

Ah ok...

I thought you meant when driving under no load.

I've never set a turbo up on idle/revving stationary.....

Not sure if I'm alone there, but it seems totally pointless! 
Need to start small, drive and adjust accordingly.

But get those gauges sorted or you could be doing damage/not getting near the potential
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#8
Cars not on the road yet guess I'm probably getting ahead of myself.

Yes is a bit pointless just wanted to see some boost to know if the turbo is any good.

It was just one of the first things that came up on a google search that it should be set at 2-5 PSI at 2K was on a different site on a different engine however.

Gauges are ordered and on the way.

Thanks for the advice guys !
Cherry red 205 XUD VNT - Project thread here http://306oc.co.uk/forum/showthread.php?tid=25522
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#9
vnt boost is set up in mapping, not by the screw stop! If you can't achieve the boost curve the mapping wants, because it can't close enough - then you start to look at the mechanical side of things (usually for vacuum leaks, rather than a screw which shouldn't be touched by the actuator under running conditions anyway)

Makes me laugh how most people seem to think you set up boost on a vnt like you would with a wastegated turbo
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#10
Mapping? It's a xud.
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#11
(28-09-2015, 08:24 PM)Chairchild Wrote: Makes me laugh how most people seem to think you set up boost on a vnt like you would with a wastegated turbo

Makes me laugh when people give advice on the wrong engine setup altogether lol
Wishes for more power...
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#12
(28-09-2015, 08:24 PM)Chairchild Wrote: vnt boost is set up in mapping, not by the screw stop! If you can't achieve the boost curve the mapping wants, because it can't close enough - then you start to look at the mechanical side of things (usually for vacuum leaks, rather than a screw which shouldn't be touched by the actuator under running conditions anyway)

Makes me laugh how most people seem to think you set up boost on a vnt like you would with a wastegated turbo

I'm forgot to mention in the first post im using a boost can to control the vnt, so there's no mapping at all, just alot of mechanical adjustments until its all setup right. 

Even if it was mapped the stop screw would need adjusting as the chra has been replaced and they have sent it wound all the way in.
Cherry red 205 XUD VNT - Project thread here http://306oc.co.uk/forum/showthread.php?tid=25522
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#13
Mine wouldn't run if it was too far out and then for about a turn barely ran. Think I set it about half a turn from the barely running point to get a good spool.

Never had an EMP gauge.
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#14
Thanks might give that a shot if I get bored before the emp gauge shows up
Cherry red 205 XUD VNT - Project thread here http://306oc.co.uk/forum/showthread.php?tid=25522
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#15
(28-09-2015, 10:36 AM)mr_fish Wrote: Get your EMP gauge on, will be easy to find a happy medium then. 2:1 EMP to Boost Ratio is what I roughly worked on, seemed to hold together and still does to this day.

This ^

Without an emp gauge on you could quite easily ra*e / b0rk the turbo if you wind it in too much
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#16
Fair enough, I'll leave it alone till I get the emp then lol.
Cherry red 205 XUD VNT - Project thread here http://306oc.co.uk/forum/showthread.php?tid=25522
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