Enter the maximum RPM of your converter and the maximum torque of the engine into the calculator to determine the k-factor.

## K Factor Formula

The following formula is used to calculate the k-factor of a stall converter.

K = RPM * Sqrt (T)

- Where K is the k-factor of the torque converter
- RPM is the converters stall RPM
- T is the engine torque output (lb-ft)

To calculate the k-factor of a torque converter, multiply the stall rpm by the square root of the torque output.

## Stall Converter Definition

A stall converter is a device used in an internal combustion engine that produces a maximum torque multiplication at stall RPM.

## Example Problem

How to calculate k-factor?

**First, determine the converters stall RPM.**For this example, the stall RPM of the torque converter is found to be 4000RPM.

**Next, determine the maximum engine torque output.**For this example, the engine can output a maximum of 400 lb-ft of torque.

**Finally, calculate the k factor.**Using the formula above, the k factor is found to be:

K = RPM * Sqrt (T)

K = 4000 * Sqrt (400)

K = 80,000