I once saw my boost gauge hitting 1.1 bar.
all i have is a FMIC, full striahgt through exhuast with decat. air filter adjustable actuator, dump valve.
it was hitting 1.1bar for about 2 weeks.
it would hit fuel cut, well i say hit i stopped before fuel cut comes in as you can feel it about to come in lol.
but if i floored it at 2000rpm - fuel cut 3000rpm fuel cut
but anything over 4000rpm it would boost to 1.1 bar dropping off to about 0.8 near the red line.
the thing would absolutely fly and the noise from the dump valve was louder than my mates impreza runing 400bhp.
on closer inspection i found that looking at my actuator i could see the line running to the back of the turbo had come off ( how i do not know )
but i shat myself so rite away got a new hose for it. and fitted it. i went for a fuel hose as its the only thing the race shop near me had. but after installing it i am running 0.5 - 0.6 bar
it runs lovely now. was it turbo oil feed or was it a boost hose. i have no idea if some one knows what i mean i wouldn't mind knowing what i fixed lol.
anyway i'd say boosting anything over 1.0 bar on standard ct9 is good fun......but at the cost of your engine !!!!!!
its not big and its not clever.