Gone 6.80's with a 1"od to the inlet of a 110 pump that feeds a -8 to the BV.
Fuel pulls faster from the center of the tube line than the fuel thats rubbing the ID of the tube. The smaller the od of the tube the larger the center fuel core there is, the larger the od the smaller the core is. This is matched to pump size and head pressure/ line length. If this was a funnycar/altered and the tank was tall and back towards the pump, 1 1/4 would work because the head pressure of the fuel is above the pump inlet and thats what is feeding the pump, but since you are much further away and the head pressure is below the pump inlet, you need a stronger draw from the tank(larger center fuel core)