Abstract: An inlet manifold system particularly adapted for a V-8 to a V-16 type internal combustion engine includes a plenum adapted to coact between supply runners and demand runners by adjusting its configuration to achieve maximum engine performance at both the high end and low end operation of the engine. The plenum is adapted for slidable movement between the open and close positions to improve communication between the supply and demand runners. In one embodiment, a slide valve is disposed in the plenum outwardly of the supply and demand runners and includes a plurality of arcuate sections joined by flat sections and vanes which overlap the spacing between pairs of adjoining supply and demand runners. The slide valve is controlled to move into a closed position to isolate the adjacent pairs of supply and demand runners and segment the plenum into separate sections each of which has a supply and demand runner having equal area openings. The slide valve can be automatically controlled responsive to the engine RPM.

Abstract: An inlet manifold system particularly adapted for a "V-8" to "V-16" Type internal combustion engine. Such an engine has a first and a second bank of cylinders.First and second elongated secondary manifolds disposed substantially parallel to and above the respective bank of cylinders;A plurality of substantially parallel, spaced apart, demand runners joined to each respective secondary manifold along its length, each demand runner extending from the secondary manifold to a cylinder in the opposite bank of cylinders and in fluid connection with the secondary manifold and the cylinder.A plurality of substantially parallel, spaced apart, supply runners joined to each respective secondary manifold along its length and in fluid connection therewith.The demand runners and the supply runners are connected to the secondary manifolds such that each pair of adjacent spaced apart demand runners has an supply runner therebetween.