What does the term “gear ratio” refer to in manual transmissions?

The term "gear ratio" specifically refers to the relationship between the input speed provided by the engine and the output speed at the wheels. In essence, it defines how many times the engine must turn to produce one complete turn of the wheels. A higher gear ratio means more torque is transmitted to the wheels, which is ideal for acceleration but may result in lower speed. Conversely, a lower gear ratio allows for higher speeds but usually at the cost of torque.

Understanding gear ratios is crucial in manual transmissions because they directly influence vehicle performance, including acceleration, fuel economy, and top speed. The correct interpretation of gear ratios allows drivers to select the appropriate gear for various driving conditions, maximizing efficiency and control.