One of them is the return line right?
We are dropping in a carbed 305 and plan on keeping the electric fuel pump setup.
Does it need a 3-port FPR or can we run a plain jane FPR and do something with the return line???
I heard a 3-port is safer and easier on the pump.

 

Yes.

 

What I really want to know is...., what needs to be done with the return line if a 2-Port FPR is used?
I shouldn't just block it off right.

 

If you retain the electric fuel pump you'll need to install a pressure regulator that can relieve the excess fuel volume back to the tank. The smaller of the two lines is generally the return line.

 

I just use a mechanical pump that bolts to the side of my block and it's just hooked up to the return line for fuel. Works great.

Brad...