Fuel presssure drop

[brickyard69]

I have a 1969 Camaro with all new tank, lines, motor, pump, and carb.

The car ran fine (100 miles) until recently.

Now it will start fine with 7 psi fuel pressure. After a 10 minute drive the car will start to die and have fuel pressure between 0-3 psi.

I tried swapping pumps and it still does it. The pump I swapped was used and I assumed it was good, but it may not be.

I removed the line from the tank to pump and notices that fuel trickled out (not poured).

I removed the tank to ensure that the "sock" was clean and there were no obstructions. There were non as everything is new.

I put my finger over the inlet hose from the pump. Should there be suction? There was none.

Any suggestions?