Horsepower Calculator

CPR Racing Technical Center

Estimate the minimum injector flow required to safely support your horsepower target.

Target Horsepower Enter your target engine horsepower.

Fuel Type Changing fuel updates the suggested BSFC.

Engine Type Boosted engines generally require more fuel.

Number of Injectors Usually one injector per cylinder.

Maximum Duty Cycle (%) CPR recommends sizing around 80–85%.

BSFC (lb/hp/hr) Editable for your engine and tuning combination.

Injector Rated Pressure (PSI) The pressure at which injector flow is rated.

System Base Pressure (PSI) Used to pressure-correct the required rated flow.