Air intake device

The invention relates to a suction device for an internal combustion engine provided with a first manifold having a slot. A first suction line is extended from an input orifice which enters the first manifold to an output orifice which connects the first suction line to the suction line of a cylinder head of the internal combustion engine. The inventive device also comprises a second suction line and a second manifold provided with a second slot which are orientable and interconnectable. When the second suction line is in the first pivoting position, intake air passes through the first slot to the first manifold and afterwards, flows to the first suction line. When the second suction line is in a second pivoting position, the first and second slots are hermetically connected to each other in such a way that intake air passes through the first slot and directly through the second slot in order to enter the second manifold and afterwards, to flow to the first suction line crossing the second suction line.