From the Edelbrock carb manual - "Avoid extremes in fuel pressure. At IDLE, there should not be any more than 6.0 psi; if the vehicle has
an adjustable fuel-pressure regulator, set it to 5.5 psi. With most fuel pumps the minimum fuel
pressure is encountered at high rpm and WOT. Fuel pressure should not drop below 2.0 psi. If it does,
a fuel pump with more capacity may be required."