Is it making noise yet? I had an old beater that had the same oil pressure, thicker oil didn't help. As soon as you reved it up a little, the OP would jump to nearly a respectable level.

I beat the crap out of that car around town for nearly 2 years before it started making noise, shortly after the noise started, it began to overheat as well.

I just had to pull the pan off before I sent it away. The rod surfaces of the crank had groves nearly 1/8" deep on the top 1/2 of the crank, and the bottom of the crank journals looked great. Pull the rod caps, and the lower journals looked normal, you had to remove the caps an turn the crank 180 degrees to see the groves. One of the strangest things I ever saw. Gene