Low Pressure Return Line PSI

[Doppleganger]

The supply line on my EFI is 56-58psi - what is the return PSI? A 30R7 line be ok? My supply lines are 30R9 - I have enough 30R7 to do the returns - 30R9 seems way overkill but I know some of these systems will have about the same PSI returning as the supply. Just curious.

 

[Ricko1966]

The supply line on my EFI is 56-58psi - what is the return PSI? A 30R7 line be ok? My supply lines are 30R9 - I have enough 30R7 to do the returns - 30R9 seems way overkill but I know some of these systems will have about the same PSI returning as the supply. Just curious.

The return side pressure is dictated by the size of the return line. If the return line is big enough the pressure is zero.

 

[Doppleganger]

The return side pressure is dictated by the size of the return line. If the return line is big enough the pressure is zero.

Its actually a size smaller - which I thought strange.