Going back to the fitting in the fuelpump
That style fitting,in my experience, is a severe restriction. It screws into the pump ok, but measure the hole inside it, and compare it to a conventional oem style fitting,with the single bubble on the end. You'll see what I mean. It'll work on your lo-po 2bbl engine, but don't try it on your HO 360. If you drill it out you'll be flirting with disaster.
I installed a 3/8 line, a 3/8 HO pump and the oem fitting. I did punch out the hole as far as I dared. I chained the engine down for limited motion and but a 3/8 steel jumper from pump to frame line, with EFI jumper hoses at each end, with no barbs, and double gear-clamped with screws diametrically opposed.I might even have looped it, can't recall. It's been good since 2004.
Point is you gotta be careful on the suction side, to avoid restrictions.
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