correct the turbo does have the ability to hold boost and i am quite sure i could make and hit 20 psi to rev limit and also don't expect it to hit and hold over 30 psi to the limit as i understand its a small turbo and is unable to hold that higher boost that high up the rev range.
but at the same time i'm confident it should not drop around 6psi just on actuator pressure.
i will test the intake system again tomorrow and report back as for power no idea its not been on the rollers yet trying to sort theses niggles first