50psi "base fuel presure" and dual walbro 255lph intank pumps. Base pressure being fuel pressure measured at zero vacuum. The fuel pressure regulator is a 1:1 rising unit, so it will raise 1psi of fuel pressure per 1 psi of positive manifold pressure/boost.
If i ran the car at a base pressure of say 70psi on the intank 255lph walbro fuel pumps and tried to get say another 30psi of fuel pressure do to the rising regulator and 30psi of boost the walbro pumps wouldn't be able to keep up.... They wouldn't even make 100psi due to the drop off of flow that is pretty drastic at pressures this high on these pumps. Another thing about these pumps is they have relieve valves on them. So what i do to cheat the sytem per say is push the relief valves in on the pumps so they wont open and add to a drop in fuel pressure. The relief valve will open around 70-75psi on them and bypass fuel if not modfied. Modifying this is a VERY easy modification that you can do in letterally 30 seconds.... It's a cheap and easy way of getting some more fuel supply out of the intank walbros that a lot of guys run.
If i ran the car at a base pressure of say 70psi on the intank 255lph walbro fuel pumps and tried to get say another 30psi of fuel pressure do to the rising regulator and 30psi of boost the walbro pumps wouldn't be able to keep up.... They wouldn't even make 100psi due to the drop off of flow that is pretty drastic at pressures this high on these pumps. Another thing about these pumps is they have relieve valves on them. So what i do to cheat the sytem per say is push the relief valves in on the pumps so they wont open and add to a drop in fuel pressure. The relief valve will open around 70-75psi on them and bypass fuel if not modfied. Modifying this is a VERY easy modification that you can do in letterally 30 seconds.... It's a cheap and easy way of getting some more fuel supply out of the intank walbros that a lot of guys run.
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