today, i removed a tiny bleed hole from my hallman evo rs. it was "built in" to the "outlet" hose barb, so i replaced it with a brass 1/8" npt 3/16" hose barb fitting i had handy.
this resulted in overall lower boost levels, as expected, but it also resulted in more stable boost. in theory, a ball/spring mbc should not work without a bleed hole, but this works not only well, but better
i ended up giving it another whole turn to put boost back to 19psi. i had to go back through my utec open loop boost map and give it a kick in the rear... almost 100 duty to get it up that high. the map now looks like this:
in the 60-100 columns. only when the 100 column is hit does the boost get limited by the hallman... at 60% it is approximately 10psi, at 90% it's 17 or so.