1. What is Fuel Pump Flow Rate?

The fuel pump flow rate is the amount of fuel (in gallons per hour) that a fuel pump needs to deliver to properly support an engine's horsepower requirements. Proper sizing ensures adequate fuel supply under all operating conditions.

2. How Does the Calculator Work?

The calculator uses the fuel pump flow rate formula:

Where:

• \( BSFC \) — Brake specific fuel consumption (lb/HP-h)
• \( HP \) — Engine horsepower
• \( Density \) — Fuel density (lb/gal)

Explanation: The formula calculates the required fuel flow based on engine power, fuel efficiency, and fuel density.

3. Importance of Proper Fuel Pump Sizing

Details: An undersized fuel pump can cause lean conditions and engine damage, while an oversized pump may lead to unnecessary fuel heating and reduced efficiency.

4. Using the Calculator

Tips: Enter engine horsepower, BSFC (typically 0.4-0.6 for gasoline engines), and fuel density (6.2 lb/gal for gasoline). All values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What is a typical BSFC value?
A: For gasoline engines: 0.4-0.6 lb/HP-h. Diesel engines typically have lower BSFC (0.3-0.5). Turbocharged engines may have higher BSFC.

Q2: Should I add a safety margin to the calculated flow rate?
A: Yes, it's common to add 20-30% to account for pump wear, voltage fluctuations, and future power upgrades.

Q3: How does fuel type affect the calculation?
A: Different fuels have different densities and BSFC values. E85 requires about 30% more flow than gasoline due to lower energy content.

Q4: What about fuel pressure requirements?
A: This calculator determines flow rate only. Pressure requirements depend on fuel system design and engine needs.

Q5: How does altitude affect fuel pump sizing?
A: At higher altitudes, engines typically require less fuel due to lower air density, but the effect is usually small for naturally aspirated engines.