Low fuel pressure after making pass down track

Electric pumps do a better job of pushing fuel, than pulling fuel (just FYI). Make sure your pump is in position to be gravity fed, also (since your tank is new) I would put my fuel filter after the pump if you are comfortable with that (mine is setup like that for my race/street car). Some folks do a course filter pre-pump (like 100µm) and a fine filter after the pump (about 40µm)...just food for thought. Also, if your sending unit has that little sock on the end of it, I would remove it. Those can cause headaches....

On the carb side, when this lower pressure event happens, is the car running? If so, do you hear anything weird like the carb loading up? The reason I ask is, you could be pushing fuel past the needle & seat and drowning the engine in fuel (with the air filter off it would look like a fountain coming out of the vent tubes).

One last thing I would check is your pump. Does it sound different when the pressure is low?