HI Steve thanks for commenting.
Regarding the boost, yes its slightly strange setup, it works well but does have some compromise.
The turbos only control is through the actuator, there no not bleed valves or manual boost controllers. THe actuator is a brand new -31 costworth garrett one rated to 8psi, it has a hefty spring on it that certainly isnt susceptible to boost creep.
What was found after pressure testing it with a handy piece of kit was that it was opening too soon, and likely to only give around 4psi at peak, which would have been no good.
The actuator was given some more preload, and the ECU was then used as a negative boost control by means of capping the throttle. i.e you punch the throttle at 3k it would normally spike to say 15psi?, isntaed the throttle is say capped to 50% to restric boost (even though your foot is flat to the floor). and this way you can control the boost to pretty much any level below the actuator setting.
The boost is purposefully bought in gradually in my case to help save the shock loading on the gearbox and clutch.
It became aparent after it was tested that
It's suprising how late your hitting full boost, on my similar set up I was hitting full boost @4000rpm even when moving upto a gt28rs/2871r I was still getting full boost @4500rpm so for yours to hit 9psi at 5500rpm is a bit poor. This could be down to you having a large turbo but is more than likely down to you just using the actuator as your boost control. You'll find that the actuator is being partially opened as the boost is building up, why don't you get a boost solenoid as this then blocks any pressure being seen at the actuator untill the pre set pressure is reached, this helps keep the actuator/wastegate closed and should allow faster spool up. I've been assured in the past by Andy at Ktec that the gen90 has this facility so it should be a fairly straight forward fit. Other things I'd definitely upgrade is the fuel system to return setup unless you've already did this since your last PM.