Port EFI experts:
I am currently plotting out the fuel system plumbing. The port EFI system is equipped with aftermarket fuel rails machined for -8 o-ring adapters. I am stepping down to -6 except at the crossover between rails. I am using an in-tank fuel pump retrofit kit which is supplied with all -6 hardware. The retrofit kit has a built in pressure regulator. Their setup dumps the excess fuel into the tank right at the adapter head mounted to the tank so only one pressure line goes to the fuel rails. It wasn’t clear to me that’s how their system was designed. I was planning to set the fuel system up using a fuel pressure line to the rails then a return line to a regular. When I asked the manufacturers of these systems they said a bypass system with a return line is better. OEMs configure their systems both ways and are now getting into PWM controlled pumps which are true returnless systems.
Question: Do I use the internal pressure regulator and run one pressure line to the fuel rails in a quasi returnless setup or buy an external regulator and run a return line from the fuel rails?
Thanks,
Mike
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