Abstract: A car having: two front wheels; two rear wheels; a bottom wall, which delimits a lower surface, which faces a road surface and, in use, is brushed by an air flow flowing under the car; an internal combustion engine; and an exhaust system, which is coupled to the internal combustion engine and is provided with an exhaust duct, which originates from the internal combustion engine and has an end chamber, which ends with an outlet opening, through which exhaust gases are released into the atmosphere. The end chamber of the exhaust duct has at least one movable partition, which can be moved to different positions so as to change the width of the outlet opening. The movable partition delimits a lower surface of the end chamber, which faces the road surface and, in use, is brushed by the air flow flowing under the car.

Abstract: An exhaust system for an internal combustion engine and having an end chamber having a first inlet opening and a second inlet opening, which are separate from and independent of one another, and an outlet opening, through which exhaust gases are released into the atmosphere; an exhaust duct, which originates from the internal combustion engine and leads to the first inlet opening of the end chamber; a silencer device, which has an outlet opening, which directly leads to the second inlet opening of the end chamber; a bypass duct, which originates from the exhaust duct in the area of a bifurcation and ends in an inlet opening of the silencer device; and an adjustment valve, which can be electronically controlled, is arranged along the exhaust duct downstream of the bifurcation where the bypass duct originates and is designed to adjust the exhaust gas flow towards the first inlet opening of the end chamber.

Abstract: A car having: two front wheels; two rear wheels; a bottom wall, which delimits a lower surface, which faces a road surface and, in use, is brushed by an air flow flowing under the car; an internal combustion engine; and an exhaust system, which is coupled to the internal combustion engine and is provided with an exhaust duct, which originates from the internal combustion engine and has an end chamber, which ends with an outlet opening, through which exhaust gases are released into the atmosphere. The end chamber of the exhaust duct has at least one movable partition, which can be moved to different positions so as to change the width of the outlet opening. The movable partition delimits a lower surface of the end chamber, which faces the road surface and, in use, is brushed by the air flow flowing under the car.