how much boost from a manual boost controller can a stock besides exhaust and intake GSX engine take? and how much gain is prodeced from upping the boost

if its a 2g its like 14 or 15psi after that the BOV leaks really bad.

dsm/mitsubishi service manuals https://www.mediafire.com/folder/5k14qlaulb9s1/dsm_mitsubishi

service manuals(my whole collection) https://www.mediafire.com/folder/ac51jwwa3g1n1/automotive_manuals

so about how much HP with it at that with say an aftermarket BOV.