MB wastegate

[quk@isham-research.demon.co.uk (Phil Payne)]

Does anyone know the boost pressure at which the MB (MC-2?) wastegate actually 
starts to open?

Also - is it possible for overboost to result from the turbo impellor retaining 
nut coming off?  We were thinking that the blades moving towards the housing 
might increase the impellor's efficiency to the point where, even with the 
wastegate fully open, there was still enough gas available at high revs to 
generate too much boost.
 
Other than that, I can't find _any_ reason for the ECU to lose control of the 
wastegate, as his seems to have done.

-- 
 Phil Payne
 UK Audi [ur-]quattro Owners Club