Just because you have a return style regulator, does not mean you are always returning fuel. I see no reason why a pump that is maxed out on a dead head regulator would not supply the engine with the same amount of fuel with a return style regulator.
If the return regulator stops returning it's because the fuel pressure has dropped below the setting, & that means the pump volume is to low.
1968 Charger COLD A/C Hilborn EFI 512ci 9.7 compression, Stealth heads, 4.10 gear A518 ODtrans 4100lb,10.93 full street car trim 2020 T/A 392 Stock 11.79 @ 114.5
