The Porsche 956 also appeared with two different rear wing designs. The cars were fitted with a larger, high downforce rear wing for most events. For the Circuit de la Sarthe at Le Mans however where top speed on the almost long Mulsanne Straight was essential, the 956 was fitted with a much lower and smaller 'low drag' wing to enable the cars to reach speeds of around . Some of the privateer teams would also experiment with a front wing attached to the cars at the tighter circuits in an effort to increase front downforce, but wind tunnel testing eventually found that these wings were disrupting the airflow over the car and actually increased the aerodynamic drag making the cars slower in a straight line. Notably, the factory backed Rothmans Porsche team did not make use of the smaller front wings. Many attributed this to the fact that the Rothmans cars used a one piece body undertray which helped increase the downforce generated by the ground effect aerodynamics while the customer 956's used a twin undertray which disrupted the air flow and slightly decreased the downforce.