Variable geometry intake manifold for an internal combustion engine

Described herein is a variable-geometry intake manifold for an internal-combustion engine; the intake manifold is provided with: at least one intake pipe, which connects the intake manifold to at least one cylinder of the internal-combustion engine; a partialization device for varying the geometry of the intake manifold that has at least one partialization body, which is set inside the intake pipe and is provided with a shaft mounted so that it can rotate about an axis of rotation; and at least one angular-position sensor, which is designed to determine the angular position of the shaft aboutthe axis of rotation and has a permanent magnet fixed on the shaft, and a reader, which is designed to read the orientation of the permanent magnet and is set on the outside of the intake pipe in theproximity of a wall of the intake pipe itself and in the proximity of the permanent magnet.