I always run light oils. I am from that side of the fence. 10w40 or 15w40. When I went to order the 10w40 Racing
oil they didn't have it in a straight racing
oil. Just a blend so with Winter coming on I went for the 10w30. 10 psi per 1000rpm is fine. The pressure in my engine is 75psi cold Idle and 40psi hot. Pressure does not indicate flow.