Found out the specs on that oil pump.Is it stock or aftermarket.At idle warm,cold to me should be 30 to 40.Higher rpm should be 40 to 60.Now if you have a high pressure pump,high rpm can be up to 80-90.Most stock oil pumps for the older bbc ran low pressure,19 warm,30 cold.Every once in a while,some oil delivery holes in the rear of the block do get restricted,either bad cast or small hole.The 454 was known for rounding off came lobes,lack of oil.
