I second Dars post. I suspect there is a quality control problem with recent Perry Pumps which affects the pump regulator. You should be able to get more fuel to the carb by using a smaller fuel line. You could also put a remote needle in the return line. If you do you would turn the needle in to make the mixture richer.

Perry makes a remote needle as well as others. Perry or some body once made an adjustable clamp that went over the return line and turning the screw would squeeze the line and restrict the return flow.