Why is it important to know my injector flow rate?

Knowing your injector flow rate is critical for engine tuning. If your injectors are too small, the engine will run lean under heavy load, leading to severe damage.

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Fuel & Efficiency

Injector Flow Rate

Q: What is injector flow rate?

Injector flow rate is a measure of how much fuel an injector can deliver in a given time period. It is usually measured in cubic centimeters per minute (CC/Min) or pounds per hour (Lbs/Hr).

Convert injector flow rates across common units.

Injector Flow Rate Conversion

lbs/hr = cc/min × 0.0948

cc/min = lbs/hr × 10.5485

Where: cc/min = cubic centimeters per minute lbs/hr = pounds per hour

Cubic Centimeters per Minute (cc/min):

Pounds per Hour (lbs/hr):

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About this tool

The BuildLockr injector flow rate calculator helps you quickly convert injector sizes. Use this tool to calculate your injector capacity between CC/Min (cubic centimeters per minute) and Lbs/Hr (pounds per hour). Whether you are upgrading your fuel system or tuning an engine, this size conversion tool ensures you match the correct specification. This helps tuners confirm they have the correct injector size to safely support their horsepower goals.

How to Convert CC to LBS/HR

Common Injector Sizes by Application:

• Stock NA: 200-400 cc/min (19-38 lbs/hr)
• Mild Turbo: 400-600 cc/min (38-57 lbs/hr)
• Performance Turbo: 600-1000 cc/min (57-95 lbs/hr)
• High Performance: 1000-1500 cc/min (95-142 lbs/hr)
• Race/E85: 1500-2500+ cc/min (142-237+ lbs/hr)
• Diesel: 300-800 cc/min (28-76 lbs/hr)
• Motorcycle: 150-350 cc/min (14-33 lbs/hr)

What is Injector Flow Rate?

Injector flow rate is a critical specification for fuel injectors, indicating how much fuel they can deliver in a given time period. This measurement is essential for engine tuning, especially in performance and modified applications.

Benefits:

• Determine appropriate injector size for engine builds
• Calculate fuel system requirements for power goals
• Ensure adequate fuel delivery under all conditions
• Optimize fuel atomization and engine efficiency
• Plan for future performance modifications

Important Considerations:

• Flow rates measured at standard pressure (43.5 psi/3 bar)
• Injector size should match engine horsepower requirements
• Undersized injectors can lead to lean conditions and engine damage
• Oversized injectors may cause poor fuel atomization and reduced efficiency
• Different fuels (E85, methanol) require larger injectors

How do you convert CC/Min to Lbs/Hr?

To convert CC/Min to Lbs/Hr, divide the CC/Min value by 10.5. You can also multiply the CC/Min value by 0.0948. Our free conversion tool does this calculation instantly.

What CC injector do I need for 500HP?

On gasoline, a 500HP naturally aspirated V8 typically requires at least 42 lbs/hr (about 440 cc/min) injectors. For turbocharged applications or E85, you will need significantly larger injectors (800-1000cc+).