High boost stumble

[Neil Swanson <75377.3445@compuserve.com>]

My thought,

Detonation.  What you may be feeling is the power fall off when the knock
sensors pull timing.  I've felt the same on other knock sensored turbo
cars.  

And since you do feel it when you raise the boost then they may be
connected.  

Also have you considered that maybe the IA3 ECU isn't dialed in for a
K24/26 hybrid?   Was it made for a stock K24 and its boost curve when you
bought it?  Your new turbo will move more air and denser air at that. 
Maybe you should contact Ned and see if it is time for the ECU to be
upgraded to the turbo.  

Neil Swanson