Pump Pressure Low / Bypass Connected To Fuel Cell

I’ve installed an A2000 (or A3000) Fuel pump, with the bypass from the pump connected to the fuel cell, along with a bypass regulator and return line at the carburetor.  The pressure is low at the pump and adjusting the bypass regulator on the fuel pump has no effect on pressure, why?

When using a bypassing regulator at the carburetor, line pressure and regulated pressure are one-and-the-same.  The bypass on the fuel pump should blocked when using a bypass regulator at the carburetor.  

The rule is, when two bypass regulators are connected to the same fuel pump, the regulator set for the lower pressure becomes the default regulator.  A bypass regulator at the carburetor makes for an excellent fuel system, so be sure to use the recommended bypass regulator like part numbers 13202 or 13212 with fuel pumps 11202 and 11215 and install a –10 AN return line to properly control pressure.