If you PM me I will send you an usefull original DB605 datasheet that cover all the engines.
As I already said all the MW50 equipped (except DB/DC and ASB/ASC) need C3 fuel,them can't run max boost without C3 and MW50.
There is a switch that enable the MW50 when the throttle is 110% open.
Probable SM/ASM could run with B4 and without MW50 but with B4 them are the same as A/AS, less boost, less power.
Clearly is quite strange that an DB605A engine could run it's max boost for 5 minutes when an DB605AM could run it's max boost (it mean with MW50) for 10 minutes.
Probable it mean that with MW50 an engine could endure more time at his max boost
