Selecting the Proper Size Injector Calculator

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.

Max Duty Cycle in % **

Required Injector Static Flow Rate @ 43.5 psi

Professional Fuel Injector Calculator

(Idle & Peak Values)


Fuel Pressure Modification Calculator

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.

Flow Conversion



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