Hi mate
I have removed mine, as I use a Blitz Boost Controller, which frankly does a better job! The boost controller uses dual solenoids to control boost, which can be set on either an RPM or Speed calibration (4 target settings). I use mine in a more simple way - set the boost, and it then tries to achieve it.
The Amal valve provides limited boost control to the ECU, but this way, the Boost is regulated by the controller, and the ECU maps to that boost.
I know that you need to be careful, as if you exceed the boost that the car has the fuel and the map to accommodate, then you will make the engine go bang! Remove the amal valve, and you remove one of the ways that the ECU can compensate.
Please correct me anybody if I am wrong!
This is in a 2WD cos
JJ