cc
rpm
%How well the cylinders fill. Roughly 80–90% for many road engines, around 100% or more for tuned engines at peak torque.
Result
Airflow5,994 L/min
How it is calculated, with your numbers
- Airflow
flow = disp / 1000 × rpm / (cycle / 2) × ve / 100999 / 1000 × 12,000 / (4 / 2) × 100 / 100 = 5,994 L/min
Working uses the metric units the formula is written in.
- disp Displacement (cc)
- rpm Engine speed (rpm)
- ve Volumetric efficiency (%)
- cycle Engine type
- flow Airflow
What it means
A four-stroke engine fills each cylinder once every two revolutions, so at full volumetric efficiency it draws its own displacement of air every second turn. Volumetric efficiency scales that up or down.
Use it to sanity-check an air filter, intake or throttle body: the parts should flow comfortably more than the engine needs at peak power.
Assumptions and limits
- Air volume at intake conditions; mass flow also depends on air density (see the altitude calculator).
Sources
- Heywood, J. B., Internal Combustion Engine Fundamentals, McGraw-Hill, 1988.