[jhein]

Originally Posted by Jay S

No matter where you put the pressure regulator fuel pressure at the pump is basically the same as the pressure at the carburetor . The only difference in pressure at different points in the system is from friction loss in the line.

It would take another regulator in the system to effect the pressure at the pump. Such as one set at 40 psi to force fuel thru a smaller line, then another to drop the pressure more for the carburetor. That would force more fuel thru a small line, it fix’s one issue, but then the fuel pump wears out sooner because it is working harder, especially without a pump controller.

Skip Fix early mentioned he noticed the fuel got hot when he had is Mallory 140 pump pushing thru a mechanical pump. That Mallory pump was a lot bigger than the mechanical pump, it is a 140 pump pushing thru a 80 pump. That was a miss match kind of similar to how the 255 pump is with 3/8” line feeding a carb.

OK, that makes sense now. So the regulator just bleeds off enough fuel through the return line to keep the pressure wherever you set it for the whole system. And I can still run a 3/8 line from the regulator to the carb, if I keep the regulator before the carb, correct? So then really, I'll have all these expensive fancy fittings for a 7 psi system? That's kinda funny.