Average Safe Boost level for a LA eng

I haven't build this eng just doing research on it. maybe next winter. but I'm learning fast, that there is a LOT to learn about turbocharging a eng........and making it survive!!!!!!
I was told that 8.0 is low these days, and that 9 to 9.5 is a better base.:study::dontknow:

NOTE: This eng would live at 6800 feet most of it's life.