Not going to reply to this thread by stating(but I am) that you must make sure the rest of the car is set up for unlimited boost.
I now run mine at 18 psi but have had a chip run and tested to 35psi with all nes to run it
These are old school cars if you want without boost control 20psi run a -34, If you want 15psi run a -31. Saying that run want you want within reason by bleeding off a certain amount .


I am not the oracle by far but my tunner/mapper has never batted an eyelid whether I was running a T4 or my current GT2871R unit.
Spark advance is set sensibly (not that I know what it is) but I been giving my car the beans for ten years with no problem.

My Best.

Tim.