Why Torque Units Need Converting
Torque specifications are commonly given in different units depending on the vehicle, equipment, manufacturer, or service manual. Automotive specifications in the United States often use pound-feet (lb-ft) or pound-inches (lb-in), while newton-meters (N·m) are common on metric specifications.
Converting the specification allows you to use a torque wrench marked in a different unit without having to estimate the setting.
Pound-Feet vs. Pound-Inches
Pound-feet and pound-inches are related, but they are not interchangeable. One pound-foot equals 12 pound-inches. This distinction is especially important with smaller fasteners, where specifications are often given in lb-in rather than lb-ft.
Always check the unit printed with the torque specification before setting the wrench. Confusing lb-ft with lb-in can result in a very large difference in applied torque.
Where Torque Conversions Are Useful
Torque-unit conversions are useful for automotive repair, engine assembly, wheels and brakes, motorcycles, bicycles, machinery, workshop equipment, and other jobs where fasteners must be tightened to a specified value.
They are particularly helpful when a service manual gives a specification in newton-meters but the available torque wrench is marked in pound-feet, or when instructions and tools use different measurement systems.
Conversion Doesn't Change the Specification
Converting a torque value only expresses the same amount of torque in another unit. It does not make the original specification higher or lower.
For example, a specification converted from N·m to lb-ft still represents the same intended tightening torque. The converter simply provides the equivalent number for the unit you need.