Not sure if anyone can help & I'm not sure if anyone will understand what I am going to describe.
Almost everytime when I shift from 2 to 3, 3 to 4, it sounds & feels like the throttle remains open for a brief sec. when I shift half way in the rev range. Never happens when I shift in low or high rpms, just in the middle. Never from 1 to 2 or 4 to 5 gears. It happens so often, I can anticipate it. Please, if anyone has an idea of what may be happening.
The cat in your uppipe is keeping pressure for a little bit and keep the turbo at higher spin (before all the pressure can exit the BOV)... If you replace your exhaust DP and UP for catless ones this should go away.