well i guess i need to speak to some mappers and turbo suppliers a bit more before going ahead.
if an external wastegate was fitted then wouldnt that limit the boost it would produce so not much fear of it spiking
also a pop off valve could be fitted at 1 or 2 psi above the desired boost level for safety,

plus if it was mapped for vanes closed but they opened then surely the egts would go down and the ecu could react??? same vise versa to