A mechanically linked valve regulates airflow into an engine’s intake manifold, controlled by a cable connected directly to the accelerator pedal. This system precisely meters the amount of air entering the engine, directly translating the driver’s input into engine speed. For example, pressing the accelerator pedal pulls the cable, opening the valve and allowing more air into the engine, thus increasing RPM.
This direct mechanical linkage offers a highly responsive and predictable feel, providing the driver with precise control over engine output. This system was the standard for decades and is still found in some vehicles today, valued for its simplicity, reliability, and ease of maintenance compared to electronic systems. Its straightforward design also makes it a popular choice for performance modifications and racing applications.