Electric Fuel pumps and mechanical fuel pumps are well specified when it comes to pressure and flow rate .Reputable manufacturers provide a curve of pressure say PSI Vs flowrate say Gallons per hour. Looking at the curve shows that max flow is available at zero pressure and max pressure is available at no flow .The real operating point is somewhere in between. Low pressure pumps being desirable for carb systems and high for injectors. The level of the fuel pump is close to the level of the tank on cars that I have seen. This means that little or no suction is demanded from the pump. Electric fuel pumps are often mounted close to the tank which is even better.
- What if the tank is very low like my jetboat?
- What if the fuel filter is above the tank ?What if the pump is after the filter which seems sensible from a pump protection viewpoint?
- How much can these pumps suck?
- Does making the pump suck give more chance of airlock problems?