I run a -12an feed line (3/4" id) with a -6an return (3/8" id) using an Aeromotive Eliminator fuel pump. When you are moving a lot of fuel you have to plan accordingly. Mine is a bit overkill, but I only wanted to build the fuel system once. Running 8 225 lb/hr Precision Turbo fuel injectors. Right now I am at 48% duty cycle at max load. I have enough spare capacity that I am going to try E-85. That should put me at about 85% duty cycle.
The plastic elbow that has the vacuum hose on it for vent is removed from the grommet. Then this: https://fuelsafe.com/catalog/cat-images/ITVV06-90.gif or similar, is installed. It fits the factory grommet. Then a 3/8" (or -6an) hose is attached and looped/coiled like mentioned. The filter on the end is a good idea.
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