I use to use a Holley blue 110 GPH electric pump between the tank and the Carter 3 valve NASCAR mechanical fuel pump on the motor without a regulator on my old NHRA 426 C.I. Max Wedge Stocker. The mechanical fuel pump will and does act as a pressure regulator
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My message is don't waste your time and money on a regulator now before trying that electric pump working in series with your mechanical pump
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A 1/2 inch O.D., 7/16 I.D. line, is fine as far as I've used for motors up to 700+ HP
![](/ubbthreads/images/graemlins/1343795-scratchchin.gif)
My new drag car will have a 5/8 O.D., #10 AN size, hardline from the pump to the pressure reg. mounted up front in front of the carb. due to shooting for 850 +HP carbureted now with EFI in the potential future for more power with a power adder later. I'll use #12 AN from the tank to the 500 GPH electric pump to start with, over build it once instead of doing it twice
![](/ubbthreads/images/graemlins/1343795-scratchchin.gif)
BTW, how many GPH is that Holley black pump rated at
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