I have a 78 304 with a fresh build. After about 5 hours on engine, once it warms up I loose oil pressure. When cold, it idles at 50 psi, once the temp rises to 180, it drops to 2-5 psi. I know its not the sender or guage, because I also have a fuel pump shut off sender on same oil port. The fuel pump does shut off, at that low of pressure. It has new timing cover, new pump, oil filter relocation, all Bulltear.

Any Help would be greatly appreciated.