In engine performance, what does "torque" refer to?

Torque refers to the rotational force produced by the engine, which is a crucial aspect of engine performance. It is measured in units such as pound-feet (lb-ft) or Newton-meters (Nm) and indicates the engine's ability to do work. When torque is high, it means the engine can produce a significant amount of rotational force, which translates to the ability to move the vehicle, especially when starting from a stop or climbing hills.

Torque is vital in applications that require high levels of power at lower speeds, such as towing or hauling heavy loads. This makes it particularly important in commercial vehicles and trucks, where maintaining momentum while under load is often necessary.

Understanding torque also helps to differentiate it from other measures of engine performance, such as horsepower or fuel efficiency. While horsepower is a function of torque and engine speed, torque itself directly relates to the force that spins the engine's crankshaft, making it fundamental to how an engine performs under different conditions.