Variable Induction System: Description and Operation

High Speed Inlet Air (HSIA) System
PURPOSE

The High Speed Inlet Air (HSIA) System can help improve the resonance induced inertia charging effect which will yield greater torque and a wider torque band under certain engine operating conditions.

OPERATION

The (upper) intake manifold (9424) contains a series of four shutter valves that are controlled by a shutter valve actuator mounted externally on the (upper) intake manifold. Opening or closing the shutter valves can alter the length of the intake air path. The shutter valve actuator is supplied with vacuum from a vacuum chamber canister mounted next to it.

NOTE: The HSIA shutter valves are integral components of the upper intake manifold (9424) and are not serviceable