1. What is the Fuel Pump Horsepower Calculation?

The fuel pump horsepower calculation determines how much engine horsepower a fuel pump can support based on its flow rate, the fuel density, and the engine's brake specific fuel consumption (BSFC). This helps ensure your fuel pump can deliver adequate fuel for your engine's requirements.

2. How Does the Calculator Work?

The calculator uses the following equation:

Where:

• \( Flow\ Rate \) — Fuel pump flow rate in gallons per hour (GPH)
• \( Density \) — Fuel density in pounds per gallon (lb/gal)
• \( BSFC \) — Brake specific fuel consumption in pounds per horsepower-hour (lb/HP-h)

Explanation: The equation calculates the maximum horsepower that can be supported by a given fuel flow rate, accounting for fuel density and the engine's fuel efficiency.

3. Importance of Fuel Pump Sizing

Details: Proper fuel pump sizing is critical for engine performance. An undersized pump can lead to fuel starvation at high RPM, while an oversized pump may cause excessive fuel pressure and heat.

4. Using the Calculator

Tips:

• Flow Rate: Typically 0.5-1.0 GPH per 100 HP for gasoline engines
• Density: ~6.2 lb/gal for gasoline, ~7.2 lb/gal for diesel
• BSFC: 0.4-0.5 for efficient engines, 0.5-0.6 for high-performance engines

5. Frequently Asked Questions (FAQ)

Q1: What is a typical flow rate for a performance fuel pump?
A: High-performance pumps typically flow 100-340 GPH, supporting 500-2000 HP depending on fuel type and BSFC.

Q2: How does fuel type affect the calculation?
A: Different fuels have different densities. E85 requires ~30% more flow than gasoline due to lower energy content.

Q3: What is BSFC and how do I determine it?
A: BSFC measures fuel efficiency. Stock engines typically 0.45-0.50, forced induction 0.55-0.65, racing engines may be higher.

Q4: Should I add a safety margin to the calculation?
A: Yes, most experts recommend adding 20-30% capacity to account for pump wear, voltage fluctuations, and future upgrades.

Q5: How does fuel pressure affect flow rate?
A: Pump flow ratings are typically at low pressure. Flow decreases as pressure increases - check pump flow charts for your operating pressure.