Last year I swapped my tranny from A4 to M6.
Before the swap I already had a Vortech supercharger and shifting at high rpm was obviously not an issue.

Now, with the M6 I notice something strange: when I shift the engine speed doesn't drop as fast as it used to be without the supercharger.
I don't powershift, it's a normal shifting between 4000 and 5500 rpm.
It's like the blower was pushing some air into the intake manifold not allowing the engine to reduce the rpm in a proper manner.
There is about 1 second delay

Is my Bosch bypass valve too small? too slow?

Do I need an adjustable bypass valve in order to reduce the spring compression?

Do I have to increase the size of the rubber hose between intake and bypass valve?
In the original Vortech configuration the bypass valve is connected to the hose that goes from the intake to the brake boost, it's rubber hose: about 2 ft long and 0.15" inner diameter (5/32").

Or is this kind of shifting just normal?

Here a picture of the engine bay to have an idea of my setup...


Thanks for every hint!

Stefano