I have posted on this before but i need to get some more opinions as to what is causing my oil pressure to never reach higher than 50psi.

I Have:
-checked the front cover oring
-replaced and shimmed the front spring
-installed a 115psi race reg
-sonic cleaned my oil cooler

I believe there is something still wrong with the cooler even after the clean as when i eliminate the cooler, by removing the bypass valve, i reach full pressure. however when i plug the bypass hole with a bolt i get the low pressure.

Thinking perhaps there was something stuck in the cooler that a sonic clean could not take care of, i bought another cooler (that was quite decrepid) and got it sonic cleaned and the problem was worse when i plugged the hole.

Is it possible that i have 2 bad coolers?
doesent the problem have to be the cooler since i reach full pressure without it?

thanks