Wouldn`t the needle bearing rockers allow more bleed out than bushed ? I`ve read that all my life!! Lowering pressure. The needles will let more oil out , lowering pressure / the way I see it .
I run the bamm ? lifters from MRL. Same oil pressure, but mine goes up w/ rpm. the higher the rpm , the more it goes up. Like clintege, I did an oil mod., and have been trying to calm it down since, w/o pulling the engine apart, may have it now.
I have heard, all my life that 10 pounds per thousand is fine, I have more than that, but not a whole bunch more at hot idle. Altho my cam/engine set up seems to like a 1150 idle. My hot 406 sbc , w/ this same came liked to idle the same way. I don`t have sleeved bores either.