is 5psi normal 4 a gts25t R33

howzit fulaz i got a R33 gts25t auto but im goin to change it to a manual i got a K&N,boost guage,BOV,18s and a few things but im only boosting 5psi is this normal. Also when im going over 70kmph and floor it as soon as it hits roughly 5500rpm it sounds like its limiting and looses power. And when i rev it highly in neutral (at lights etc) it stalls.

my Manual 25T boosts to around 9psi stock sounds like you got a problem