Wasn't the special OEM fuel filter used on the original cars suppose to be a vapor seperator? Not for liquid returns is what I remember
I never heard of a return line to the tank, vapor can like Cab said, could be broke and just circling back to pump. Hemi cars came with 3/8 line. That stock pump "should" pump enough fuel for the carbs, cover the lines from heat to stop vapor lock. My two cents.
The sock in the tank will separate water until
its totally under water.. but its not 100%..
the return just has a orifice.. pretty sure back
then it was .060
EDIT
Yes they did have a return to the tank... any of
the so called performance engines had a return..
any that had a 3/8 supply had a return
