This calculates the cubic feet per minute (cfm) of air that an engine will consume at its maximum rpm. This is a great tool for estimating carburetor or throttle body sizing to avoid going either too small or too big (which is a common mistake).
**Check out our quarter mile calculator
| variable | description |
| cubic inches | the total displacement of the engine in cubic inches (see our cid calculator) |
| max rpm | the engines maximum rpm limit |
| volumetric efficiency | the volumetric efficiency is a measure of the efficiency of the engine moving the intake charge into the chamber and the exhaust out. Typical values are as follows: 2 valve head – 80% 4 valve head – 88% it is not unusual however to have VE’s of 95% or more in correctly built race engines |
| cubic feet per minute | the total cubic feet per minute of air that the engine will consume |
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