Fuel & Efficiency

Fuel Flow Rate

Q: How does fuel flow affect horsepower?

An engine requires a specific fuel flow rate to safely produce horsepower without running lean. If your fuel flow rate is too low, you risk severe engine damage.

Calculate fuel system flow requirements.

Fuel Flow Rate Conversion

L/h = gal/h × 3.785

gal/h = L/h × 0.264172

Where: gal/h = gallons per hour L/h = liters per hour

Gallons per Hour (gal/h):

Liters per Hour (L/h):

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About this tool

The BuildLockr fuel flow rate calculator helps builders determine exact fuel delivery needs. Use this tool to calculate pump flow between LPH (liters per hour) and GPH (gallons per hour). Whether you are upgrading your fuel pump or calculating consumption, this flow rate conversion tool guarantees precision. This helps users verify their fuel system can support their engine's horsepower demands safely.

How Does Fuel Flow Affect Horsepower?

Typical Fuel Flow Rates:

• Small Aircraft: 5-15 gal/h (19-57 L/h)
• Light Aircraft: 10-25 gal/h (38-95 L/h)
• Performance Car (WOT): 20-40 gal/h (76-151 L/h)
• Race Car: 30-80 gal/h (114-303 L/h)
• Marine Engine: 15-50 gal/h (57-189 L/h)
• Generator: 1-10 gal/h (4-38 L/h)
• Industrial Engine: 10-100+ gal/h (38-379+ L/h)

What is Fuel Flow Rate?

Fuel flow rate is a measure of how quickly fuel is consumed by an engine, typically expressed in gallons per hour (gal/h) or liters per hour (L/h). This measurement is particularly important in performance tuning, aviation, and marine applications.

Benefits:

• Calculate operating costs for engines and vehicles
• Determine fuel requirements for specific missions
• Optimize engine tuning for efficiency or performance
• Plan fuel logistics for racing or aviation
• Monitor engine health and performance trends

Important Considerations:

• Higher flow rates indicate greater fuel consumption
• Flow rate varies significantly with engine load and RPM
• Critical for calculating range in aircraft and boats
• Used in engine tuning to optimize fuel delivery
• Environmental conditions affect actual consumption

How do you convert LPH to GPH?

To convert liters per hour (LPH) to gallons per hour (GPH), multiply the LPH value by 0.264172. You can also use our free flow rate calculator to instantly convert values.

Is a 255 LPH fuel pump enough for 500hp?

On standard gasoline, a 255 LPH pump can typically support up to 500-550 horsepower at the crank under normal base pressures. However, if running E85 or high boost, a larger pump (like a 340 LPH or 450 LPH) is required.