Flow Calculator

Looking for 500 horsepower to the rear wheels? How about 1000 horsepower at the crankshaft? You can determine what size fuel injectors you will need by entering a few simple details into our calculator. Explanations of each input are below the calculator.

The inputs are, in order of appearance:

The number of cylinders in your engine,

The BASE* fuel pressure you will run (your fuel pressure at idle), *our calculator assumes a 1:1 rising rate fuel pressure regulator for turbo applications

Engine aspiration, {Turbocharged, Supercharged, and Naturally Aspirated engines have different BSFC’s (see Glossary of Terms for definitions)}

Desired horsepower, (The amount of power you desire directly affects the amount of fuel you will need to achieve your goal.)

Maximum injector duty cycle (IDC) (In order to be conservative, Fuel Injector Clinic recommends a maximum duty cycle of 90%.)


Horsepower desired
Injector Size Required
Fuel Type cc/min lb/hr