Understanding Fuel Pump Sizing
This calculator estimates the fuel pump flow rate needed for your vehicle based on engine horsepower, fuel type, and fuel system type. Proper sizing ensures your engine gets enough fuel for optimal performance without starvation.
Fuel flow is calculated using pounds per horsepower per hour (lb/HP/hr), adjusted for fuel type and system. For example, gasoline requires about 0.5 lb/HP/hr for naturally aspirated engines, while forced induction or E85 increases demand. Results are converted to GPH or LPH using fuel density.
Fuel Pump Flow Rate Examples
| Horsepower (HP) | Fuel Type | System Type | Flow Rate (GPH) | Scenario |
|---|---|---|---|---|
| 300 | Gasoline | Naturally Aspirated | 25 | Street performance car |
| 500 | E85 | Forced Induction | 49 | Turbocharged drag car |
| 700 | Diesel | Naturally Aspirated | 40 | Heavy-duty diesel truck |
How to Use the Fuel Pump Calculator
- Enter the engine horsepower (HP).
- Select the fuel type (Gasoline, E85, Methanol, Diesel).
- Select the fuel system type (Naturally Aspirated or Forced Induction).
- Select the flow unit (GPH or LPH).
- Click "Calculate Fuel Pump Flow Rate" to see the estimated flow rate.
Fuel Pump Flow Rate Comparison
Estimated flow rates for different horsepower (Gasoline, Naturally Aspirated).
Frequently Asked Questions
Why is proper fuel pump sizing important?
A correctly sized fuel pump ensures your engine receives adequate fuel for performance, preventing fuel starvation that can cause misfires or damage.
Should I oversize my fuel pump?
Yes, oversizing by 10-15% provides a safety margin and supports future upgrades, but avoid excessive oversizing to prevent fuel system issues.