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Hello,
I am trying to decide how to best get the stop screw proper on my xman vnt17. It is off and I know it because xman had me adjust it, and it has never been right on VCDS so I keep playing. 6 months later im giving up! Currently, the stop screw is backed out of the CHARA pretty far maybe 4 threads sticking up.

I have no logs currently because they are not worth doing and perhaps dangerous to try because of the way the turbo is boosting. EGT is high.
The stop screw is wrong for sure, so car is A DOG .

* My general thought now is that making the stop screw shorter (as if you were to remove it completely) should increase turbo spool unless it is too short. Making it longer (clockwise into the turbo) should prevent overboost. However, I know this is grossly wrong so please correct me!

Next, I use the vac method for the actuator open around ~3hg stop between 18-20 hg and that NEVER works. So i adjust the arm length with vcds and my boost gauge trying to make sure it's not spiking and still getting decent spool. I can't get the car to run alright returning 47 MPG on long road trips driving 70-80 MPH

Currently, I am getting poor spool and the stop screw is pretty short as is the actuator. The car has no power untill 3200RPM. my setup should be close to 190 HP and it feels that way when you get the boost kicking in at 3500 RPM but it be nice to get the tires to spin again.

SO more back story,
I have been having issues for almost a year now after fitting eurojet FMIC, stage 2 cam, xman vnt17/22 turbo, pd150 nozzles, and a fader tune.

Before the turbo swap, the car would spin the tires in 1st. Since FMIC turbo and cam. Since the turbo the car is laggy and the tires will NEVER spin I have a LSD remanned transmission installed too! I expected the tune and nozzles to pick up for it but it did not. I contacted both xman and fader many times and have provided many logs never has either been able to provide me a solution. Honestly I suspect the tune is the real issue, however, I have created a bigger issue by tampering with the stop screw.

Xman had me adjust the stop screw for the lag. ITs commonly said they have turbos that are not set up correctly. This is why I am here. I know its out of wack because I messed with it. So what is the way for someone with no access to a flow bench to set up the stop screw correctly? currently, I have fiddled around a lot and been able to get decent results, but the tires still do not spin! So, I am guilty of messing it up trying to fine tune it and would like some general direction on as to how to setup the stop screw (turbo on car for now)

PS I have read this entire thing and many others Adjusting stop screw on recon GT1749VB

Thanks in advance.
 

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Imho with all the stuff you've changed to get more power out of the engine, i would take it to a tuning shop with an RR and have them remap the car properly for the hardware you are running. That will sort it out as they'll soon notice the turbo isn't boosting right and they'll dial the lot in right. you'll probably endup with more power too so it's a win win. It might be expensive but once you've changed so much you can't expect a generic fadr ecu to take into account the way the turbo boosts especially if it's not set right from the get go. Also your not the first to experience the x-man turbo not being setup right, i have read more people omplain about it but usually it is the sheer amount of changes of hardware for more go that makes it worse.
 
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