try wire'in up the actuator, and in say 3rd /4th gear bring boost in usin the brakes and throttle, (be carefull, dont cook the brakes, or do it for more 5-10 seconds, and dont go past 25/30 psi boost)

if even at 4.5 k rpm still not hitting proper boost then, could have

blocked zorst,
crack in turbo, or mani leak,
air leak, have you pressure tested whole system to 30 psi?
cam, or cam timin problem