INTAKE MANIFOLD TUNING VALVE ASSEMBLY
The tuning valve (rotary solenoid device) is electrically controlled by the PCM based on RPM and TP signal inputs, for accurate switching capability at optimum switching points to enable either a "split" or "single" plenum condition.
During low and high end of the RPM range, the PCM de-energizes the valve and enables a "split" plenum condition that provides for peak torque along with increased peak horsepower.
During the mid RPM range, the PCM energizes the valve, thus enabling a "single" tuning plenum condition that provides for mid RPM range peak torque.