The '33 runs ~6psi stock. I've had mine at 11psi, however most of the posts I've seen say 12psi is the max you should go on stock turbo.
I used to live in lonny, but moved to Christchurch 2 1/2 years ago. Skyline heaven! Got a '97 R33 25t and an '02 NZ New R34 GTt (22,000Kms and still under new car warranty:D). The son-law who lives in Lonny got to drive the GTt when he was over here on holiday. Bugger still likes his HSV's though. Needs to be re-educated.