Flow Rate Calculator

Please fill in the Number of Cylinders and the Target HP.

Number of Cylinders
Target HP @

GASOLINE

Naturally Aspirated

90 lb/hr
943 cc/min

Super-Charged

90 lb/hr
943 cc/min

Turbo-Charged

90 lb/hr
943 cc/min

RACE GAS

Naturally Aspirated

90 lb/hr
943 cc/min

Super-Charged

90 lb/hr
943 cc/min

Turbo-Charged

90 lb/hr
943 cc/min

E85 (ETHANOL)

Naturally Aspirated

90 lb/hr
943 cc/min

Super-Charged

90 lb/hr
943 cc/min

Turbo-Charged

90 lb/hr
943 cc/min
Injector flow-rate recommendations are calculated assuming a base fuel pressure of 3 Bar (43.5 psi) and a maximum injector duty cycle (IDC) of 80%.

 

When do you need larger injectors?

When you modify the original OEM engine components, i.e. bolt-ons; exhaust, headers, throttle-body, intake, air-intake; turbo kit, supercharger; internals, pistons, camshafts, etc.; any and all aftermarket parts that have the potential to raise the engine's horsepower rating.

When retuning or remapping your engine control unit (ECU) there is a potential for a generous horsepower increase.  This is a good time to calculate for higher flow rate fuel injectors.

Through tuning or a pulley upgrade on any engine factory-equipped with a turbo- or super-charger, or installing a larger turbo- or more powerful super-charger, higher flow fuel injectors should be considered as part of this upgrade.  More air to the engine necessitates an increase in fuel to maintain desired Air/fuel ratio (AFR).

The fuel injector flow must be matched to the airflow requirements of the engine over the entire rpm operating range.

The injectors must be able to supply a large amount of fuel at wide-open throttle to prevent high rpm lean out, and transitional amounts to cover all of the operating conditions in between.  This is why FiveoMotorsport flow-balanced and matched fuel injector sets are so important for overall engine performance.

Through proper tuning and possible upgrades to other components, namely the MAP/MAF in extremely modified engines your tuning-professional will be able to accomplish an OEM-like stoichiometric air/fuel ratio (AFR).

Get it right.

The Fiveomotorsport flow-rate calculator is based on potential and/or actual engine horsepower.  Depending on the option you choose, the calculator can be based on wheel horsepower or power to the crankshaft.  Because of the variable percentages lost with; front and rear, 4-wheel or all-wheel drive, we can make slight adjustments when needed.

Also note that the our flow-rate calculator assumes a base fuel pressure of 3 Bar (43.5 psi) and a maximum injector duty cycle (IDC) of 80%.  This leaves some additional room for boosted performance and keeps us below a 90% maximum threshold. 

We use the 3 Bar (43.5 psi) pressure rating and 80% IDC because nearly every OEM and upgrade EFI system in the auto industry also use these factors.

If you still have questions regarding the Fiveo flow-rate calculator, please contact us.