Sounds like your tank isn't vented enough and when running the car your building up a vacuum in the tank causing the fuel to be drawn back into the tank from the lines when the engine shuts down. Check you fuel filler cap. If the cap is really old or original, it's worth the $10 for a new one.
Also, I'd like to address the few that are persistent on swapping "the Edelbrock clone" to a Holley. First, The Street Demon carb is not a clone, it is a completely new design. Second, Holley owns Demon Carbs, and has for the last decade, so if your shitting on Demon Carbs, your also shitting on Holley. That is all, thank you!
