safe psi on a n/a turbo'd

depends on your engine managment. I ran up to 15psi, but had problems when the vacume line popped off the fuel pressure regulator, which made fuel pressure drop by 15psi. :notnice:
Otherwise, it worked fine.
 
Jaime off TF has a DP-DIS 2.3L (88 'TC with a IHI) with the turbo set up running 17psi. When we got it up to 18psi the turbo buzzer would hit and it would detonate on us. I'm not sure how he does it with the high compression motor but its a fun car to cruz around in as long as your under 18psi :)