This document should help you. I wont promise the speeds are 100% accurate because in bombers your fuel load out bombay doors and bomb load can effect speed.
I recommend you punch to max manifold untill you get the speed my document says then said your manifold as designated. Get about 5 or more miles from target to get a constant speed. (as i said you must allow a few MPH because of loadout and such.)
this should give you rough idea of what speed you should be going at what alt and with what manifold.
was gonna keep it for only squad use but here you go
http://ftp://yuccah:cwjqhn@yuccah.netfirms.com/www/bomberspeed.doc
