Torque and Power Curve Analyzer
Enter RPM and torque points. The chart calculates power automatically and identifies peak values.
| RPM | Torque (N·m) | Power (kW) | |
|---|---|---|---|
| 46.08 | |||
| 81.68 | |||
| 117.29 | |||
| 141.37 |
Engine Comparison
| Engine | Power (kW) | Torque (N·m) | Displacement (L) | Mass (kg) | |
|---|---|---|---|---|---|
Saved Engine Profiles
Formula Used
Power from torque: kW = torque in N·m × RPM ÷ 9549.296596.
Imperial power: horsepower = torque in lb-ft × RPM ÷ 5252.113.
BMEP: mean effective pressure is derived from torque, displacement, and engine cycle.
Airflow power: fuel energy equals fuel mass flow multiplied by heating value. Brake power applies thermal efficiency.
Vehicle resistance: aerodynamic drag uses one-half air density, drag coefficient, frontal area, and speed squared.
How to Use This Calculator
- Select the calculation method that matches your available measurements.
- Choose suitable units before entering torque, power, pressure, mass, or temperature.
- Enter realistic efficiency, loss, airflow, or environmental values.
- Press the calculation button and review the results above the form.
- Use CSV, printing, saved profiles, comparison, and curve tools when needed.
Understanding Engine Power Results
Power and Torque
Torque describes rotational force at the crankshaft. Power describes how quickly that torque performs work. Engine speed connects both measurements through angular velocity.
Crank and Wheel Power
Brake power is measured at the engine crankshaft. Wheel power is measured after transmission and drivetrain losses. Estimated losses vary with tires, temperatures, lubricants, and test methods.
BMEP and Specific Output
BMEP compares engine torque without favoring larger displacement. Power per litre shows output density. Both values help compare engines with different sizes and operating speeds.
Boost and Airflow
Boost increases manifold pressure and potential air mass. Compressor heat and pressure losses reduce the ideal gain. Intercooling and volumetric efficiency strongly affect practical output.
Fuel and Thermal Efficiency
Fuel energy input exceeds mechanical output because engines reject heat. Brake-specific fuel consumption compares fuel use with useful power. Lower values generally indicate stronger operating efficiency.
Accuracy and Safety
Calculated results depend on accurate inputs and realistic assumptions. Estimated outputs do not replace calibrated dynamometer testing. Engine modifications should be verified by qualified professionals.