Quote: Challenger1 is right on the money. The vapor separator is designed to provide a return to the tank. MY 70 Cuda 318 came a return connected to the separator.
Mopar started addressing the vapor lock problems back in the mid 1960s on the street hemi cars and other Hi Po models with the fuel filter vapor return lines. My wifes 1986 Ram 250 van has a 318 in it with this fuel filter You can buy them at almost any parts house, buy one and try it mounted between the fuel pump and the carb.
You can buy them at almost any parts house, buy one and try it mounted between the fuel pump and the carb. 
