CHEMISTRY CALCULATORS
Air-Fuel Ratio (AFR) Calculator
Determine your engine’s air-to-fuel ratio for optimal performance.
What is the Air-Fuel Ratio (AFR) Calculator & How does it work?
The Air-Fuel Ratio (AFR) is a crucial metric in internal combustion engines, indicating the proportion of air to fuel mixed during combustion. An ideal AFR ensures efficient combustion and maximum power output. The formula to calculate AFR is:The constant 14.7 is used because at standard atmospheric pressure and temperature, one mole of air weighs approximately 28.96 grams, and the stoichiometric AFR for gasoline engines is around 14.7:1.
text{AFR} = frac{text{Volume of Air}}{text{Mass of Fuel}} times 14.7
AFR = Air-Fuel Ratio, Volume of Air in liters, Mass of Fuel in grams
Parameters
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Frequently Asked Questions
What is an ideal AFR for my car?
An ideal AFR varies by engine type, but for most gasoline engines, it ranges from 14.7 to 16:1.
How do I measure the volume of air in liters?
Measure the volume of air using a displacement syringe or calculate it based on engine displacement and RPM.
What does the constant 14.7 represent in the AFR formula?
The constant 14.7 represents the stoichiometric ratio of air to fuel for gasoline combustion at standard conditions.
How can I adjust my AFR for better performance?
Adjust your AFR by tuning your carburetor or using a fuel management system to achieve optimal engine efficiency.
What is the difference between lean and rich AFR?
A lean AFR has more air than fuel, while a rich AFR has more fuel than air. Each can affect engine performance differently.
Can I use this calculator for diesel engines too?
Yes, but note that the ideal AFR for diesel engines is different, typically ranging from 14.5 to 16:1.
How does temperature affect AFR calculations?
Temperature affects air density and volume, so ensure your measurements are taken at standard conditions or adjust accordingly.
Results are for informational purposes only and do not constitute professional advice.