An automobile comprising first and second flaps provided on either side of a centerline on the underside of the automobile is provided. Each flap is deployable from first positions that extend minimally into the flow to respective second positions where each flap extends maximally into the flow of air when the automobile is in motion to reduce the downforce generated by the automobile. A control unit adapted to receive inputs that indicate the dynamic state of the automobile is further provided. The control unit select positions of the first and second flaps depending on the dynamic state to control the downforce generated by the automobile. If the inputs indicate that the automobile is cornering, the positions of the first and second flaps are selected so as to counter roll of the automobile.