Adjustable Internal Wastegate Issues

[Freise]

I've got an Isis RS3871, it comes with an adjustable internal wastegate, supposedly adjustable from .5bar to 1.5bar.

I didn't realize it came with an adjustable wastegate, so when I figured that out I decided to do the research, learned that the way you adjust it is by extending the actuator arm to lower boost, and shortening it to raise boost. Everything that I look at suggests that the lengthen/shortening of the actuator arm controls boost by pre-loading the spring. If the spring is slightly compressed (rod shorter) = more boost pressure to open wastegate and vice versa.

Anyways, so I leave the arm in the "stock" setting to see where I'm starting from. I do a 5th gear low rpm pull so that I can watch boost slowly increase, make sure everything is safe. It begins spooling and by about 2800 reaches about 11psi and stops climbing, took it to about 3500rpm.
I try a 2nd gear run, and as soon as I hit the throttle boost goes right past 11, let off at 19psi

My first assumption is maybe I just wasn't able to spool it past 11psi in 5th gear due to low rpm, so I adjust the rod, and lengthen it by about 6 rotations. I do a 5th gear pull again, this time it hits about 8psi and stops. Do a 2nd gear run and it flies right past 8, keeps going up! Let off at 16+!

So i tried adjusting the length of the actuator arm to where it is parallel with the wastegate flap. In other words, there is virtually no tension on the arm. I assumed this is the lowest boost setting. Again, 5th gear run, I'm pegging 5psi. But as I push higher rpms, it flies past 5psi and keeps climbing, I can easily take it up to 15psi or more.


If I lengthen the actuator arm any further, the wastegate flap will not sit closed. Is that something I'm going to have to live with in order to see less boost??? Or does it sound like the wastegate isn't working right? (FYI did extensive boost leak test, no leaks!)


TL;DR Turbo will hit a "limit" of boost in lower rpms, will keep climbing very quickly in higher rpm. Not sure if I don't understand basics of adjustable wastegate or wastegate is broken in some manner.