What boost level is safe for a stock RB26DETT?

The factory RB26DETT runs around 10-11 psi (0.7 bar) from the stock ceramic twin turbos. Most tuners consider 14-16 psi (0.95-1.1 bar) the safe ceiling on stock internals with upgraded turbos and a proper tune, producing 350-400 whp. Beyond that, forged pistons, rods, and a head stud kit are strongly recommended. The RB26 block is robust; the stock rod bolts and head gasket are the weak points at elevated power levels.