fuel questions

[northstar ninja]

I read the fsm about the dual fuel pump setup in the 260z. it doesn't give a flow rate for the electric pump, but it says the mechanical pump should run 5psi.since the mechanical pump doesn't work, I bypassed it and bought an electric pump that maxes out at 7 psi.

The question: will the 2psi difference be too much for the carb needles, or will the extra fuel simply go back to the tank via the return line?

[evildky]

which carbs are you running? the early SU's take only 2-3 psi, any more and the needle valves on the fuel bowls get overpowered and fuel comes out the fuel bowl vents like a fountain, what matters is line pressure, and weither it overpowers the nedle vavles, you can either hook an inline gauge in the fuel line or turn the car on and watch the float bowls, if the car can run without spurting gas out the fuel bowl vent tubes