So there's an internal pressure bypass inside that fuel pump? What was the reasoning? Did it prevent vapor lock or solve a flooding problem? I'm not running the stock '80 carb anyhow, it's getting replaced by a new Holley 350.
I wonder if I should change to an earlier pump that simply supplies fuel & eliminate the return. I was planning to move the vapor cannister to the rear & shorten the line up anyhow so I can remove the return while I'm at it.