3 port fuel filter

3 port fuel filter with  3/8" In Port   -   3/8" Out Port   -   1/4" By Pass and Vapor Port. Some Part Numbers to help you find one.  This can be used with electric fuel pums to keep the fuel cool in the engine compartment where temps can be 200 plus degrees.
Wix-33901   ACDelco-GF98   Powerflow-95041   Balwin-BF887   NAPA-3041   Hastings-GF20   Fram-G18   Motorcraft-FG12   Purolator-GF1118   These may need to be ordered as they are no longer a fast moving item in most stores.  The 5/16" size is much more common.

Another option (instead of using a 3 port fuel pump)  is a 3 port fuel filter after the pump.  These were used on Large Engine GM Trucks, Ford Trucks and Jeep in their hot fuel packages.    The small, or return port must be installed on top(or UP)  so vapor is returned to the tank.  Putting it on the bottom will trap vapor.   Your Fuel Pump can handle this circulating flow very easy. 

 When you think about it, we really do not use very much fuel as we travel with our units. Therefore, there really is very little fuel flow through the fuel lines, basically stagnating and just sitting in the fuel line and pump. The fuel heats up at the pump and the lines leading to the pump near the engine. During this time, the fuel can vaporize and when it is in a gaseous state it simply pushes back and forth through the intake check valve of the fuel pump. The fuel pump cannot deliver sufficient fuel to the carburetor as required by the engine.

By keeping some fuel flowing through the fuel pump and low pressure fuel line, the temperature of the fuel pump, and fuel is significantly lowered and vaporization is avoided.