fuel problem

[sgt1022]

I have a 71 c10 w/350ci edelbrock carb Holley 110 gph blue pump through regulator at 4 psi. With braided-6 line. After I drive for an hour or so in traffic my regulator starts dropping pressure when I'm at idle. The problem has left me stranded twice. I can loosen a fitting and in a couple seconds fuel starts flowing again and truck starts immediately. My fuel lines are a fair distance away from exhaust heat. I do not have a return line.