Engine VE Calculator

Speed-density volumetric efficiency, cylinder fill, and estimated horsepower / torque from mass airflow, manifold pressure, and intake air temperature.

Engine

Number of cylinders

Engine displacement

Engine speed (RPM)

Needed to relate mass airflow to cylinder volume (VE, load, torque).

Operating Conditions

Mass airflow (MAF)

Manifold absolute pressure (MAP)

Intake air temperature (IAT)

Horsepower assumptions

Fuel / injection preset

Crank hp per lb/min of airflow

Rule-of-thumb gasoline conversion (~9-11 hp per lb/min at typical AFR/BSFC). Pick a preset above or type a custom value.

Drivetrain loss (%)

Flywheel-to-wheel power loss. Typical: ~10% FWD, ~15% RWD manual, ~15-20% AWD/auto.

Load & Efficiency

Engine load / cylinder fill

189.4%

Air mass vs. naturally-aspirated baseline (101.325 kPa, 25°C)

Calculated VE

80.0%

Air mass vs. theoretical fill at manifold pressure & temp

Reference Air per cylinder per stroke

0.72g

4 cylinders, 0.600 L each

Actual Air per cylinder per stroke

1.37g

4 cylinders, 0.600 L each

Estimated Power & Torque

Flywheel horsepower

344hp

Flywheel torque

317lb-ft

@ 5,700 rpm

Wheel horsepower

292hp

after 15% drivetrain loss

Wheel torque

269lb-ft

@ 5,700 rpm

Estimates use the speed-density equation (VE = actual airflow ÷ theoretical airflow at manifold density) plus a rule-of-thumb hp-per-lb/min airflow conversion for gasoline engines. Real-world VE, BSFC, and drivetrain loss vary by engine, fuel, and setup — treat these numbers as a starting estimate, not a dyno result.