The only thing i can tell you about this question, is that if you decide to venture into anything above 5 psi, make sure u replace the head gasket, it is the weakest part in our engine.
And it sounds like u'r getting up there in the compression, time to think about timing retart.
>some have run 10 no problems and some have blown up on 5 its >all in the tuning and getting a good stock engine, its all >luck really
Stock fuel/stock internals. 10psi MAX!! It has nothing to do with luck, its making sure what your doing isnt causing any damage. Before you up the boost, do a compression test. After a week at the higher boost level do another one to make sure the boost isnt causing any damage. I raced a TT Supra a week ago with a couple mods (stock boost) and i was a car behind at 120mph...we started at around 50mph. I was running 5psi at the time.