read on another forum that on the PD130 engines the turbo is variable vane. this is used to control the boost therefore a wastegate probably wouldnt do anything.
as i said i read it on another forum so im not sure wether its the case or not.
i also heard though that ALL turbo engines, be it petrol or diesel, have a wastegate to prevent too much boost, but diesels have internal wastegates rather than disposing of te pressure externally.
 
hmmm wel i may cal allards and see what they have to say as i think it would sound pretty cool as long as it doesnt go off evety time i take my foot off the accellerator when driving steady.