The carb is right out of the box. Like I said, it runs great until the fuel pressure starts to decrease.

In an attempt to isolate the problem I removed the in-line fuel filter (between the tank and the fuel pump). I still experience the same symptoms.

I plan to disconnect the fuel line from the fuel tank and feed the fuel pump directly from a separate fuel container just to be sure that the problem is not in the gas tank.

I am also considering going to an electric fuel pump.