Fuel Injector and Pump Flow

This calculator will determine an injector and fuel pumps required flow. Input the engines peak horsepower rating at the crank, the number of injectors, the injector duty cycle (.8 or 80% is standard), the pressure the injectors are rated at (43.5 PSI is typical), the Brake Specific Fuel Consumption (this is usually .5 for N/A, .55 to .6 for supercharged, and .6 to .7 for turbocharged engines), and the fuel rail pressure (also typically 43.5 PSI). From this inector flow and fuel pump required freeflow can be determined. The fuel pump calculator leaves an extra 30% of the flow to be bypassed and calculates at 100% duty cycle which is typical.