My fresh rebuilt 270 pegs 60 psi at fast idle cold and once warmed up it stays at 20 psi hot idle.
This is my second rebuilt 270 and my other was the same with oil pressure. My rebuilt 228 also had the same oil pressures. My 302 is at 50 psi cold fast idle and 15 hot slow idle.
That old timer you mentioned might know engines but I'm not so sure he knows these great old gmc engines.
