Fuel Flow Chart



Flow conversion

Convert cc/min to lbs/hr


Convert lbs/hr to cc/min

Selecting the proper size injector

Fuel Injector Size Calculator
Horsepower (at the flywheel)
Number of Injectors
B.S.F.C. *

Max Duty Cycle in % **

Required Injector Static Flow Rate @ 43.5 psi lb/hr


This guideline can help in determining what injector size to use.

* Brake Specific Fuel Consumption: is the amount of fuel consumed (in lbs. per hour) for each horsepower made. This should be .45 to .50 for naturally aspirated engines, .55 to .60 for supercharged engines, and .60 to .65 for turbocharged engines.
** Maximum Injector Duty Cycle should be around 80% max for safe operation. This allows for some future horsepower increases.

Fuel Pressure Modification

By changing your fuel pressure, you can change the flow rates of your injectors.
For example: An injector that flows 330 cc @ 40 psi will flow 369 cc @ 50 psi.
Fuel Flow Calculator

Old Pressure

New Pressure

Old Flow Rate

New Flow Rate