Enter the air-to-fuel ratio and the fuel flow rate into the calculator to determine the engine mass air flow.

Engine Mass Air Flow Formula

The following formula is used to calculate an Engine Mass Air Flow.

  • Where EMAF is the Engine Mass Air Flow (lbs per hour)
  • ATF is the air-to-fuel ratio
  • FF is the fuel flow rate (lbs per hour)

To calculate the engine mass air flow, multiply the rate of fuel flow by the air-to-fuel ratio.

What is Engine Mass Air Flow?


Engine Mass Air Flow is a measure of the total mass of air that passes through an engine per unit of time. These units are typically pounds and hours respectively.

How to Calculate Engine Mass Air Flow?

Example Problem:

The following example outlines how to calculate Engine Mass Air Flow.

First, determine the air-to-fuel ratio. For standard engines this should be around 12.6:1. For this example, we will use this value.

Next, determine the rate of fuel consumption. For this example, the fuel flow is 30 pounds per hour.

Finally, calculate the Engine Mass Air Flow using the equation above:


EMAF = 12.6 * 30

EMAF = 378 pounds per hour