was the car n/a to start? did you wire up the map sensor got a l67? or wire up the bbv actuator? i think one of those are preventing your boost.

iirc if you pull the vac line off the bbv that will also allow full boost if the actuators not wired in.

is your pcm tuned? you need to tell your pcm theres a sc present or it wont make much boost either.