System for controlling and guiding air flow through the engine compartment of a motor-vehicle

A motor vehicle is provided with a conveyor structure (9) that conveys the entire flow of air that traverses the radiator (7) downwards and then longitudinally underneath the floor panel of the motor vehicle, preventing said flow from traversing the engine compartment and obtaining a consequent reduction in the aerodynamic resistance of the motor vehicle. Associated to the aforesaid conveyor structure (9) are active and passive fins (16, 19) for enabling an adequate cooling of the components of the engine unit or electronic components associated thereto during given operating conditions.