These components are designed to prevent a vehicle from lifting its front wheels excessively during rapid acceleration. Typically found on high-performance automobiles used in sanctioned racing environments, these extensions provide a stable contact point with the track surface, limiting upward rotation around the rear axle. The system usually consists of a horizontal bar extending rearward, supported by small wheels or skids. For instance, a vehicle producing extreme torque at the starting line can experience substantial front-end lift; these bars mitigate this, maintaining control.
The primary advantage is improved vehicle stability and control during the launch phase of a race. This leads to more consistent and predictable performance. Historically, such devices evolved alongside the increasing power output of racing engines. As vehicles became capable of generating greater levels of torque, the need for a mechanism to manage excessive front-end lift became apparent. The use of these devices helps to prevent dangerous situations, such as complete vehicle rollover, and allows drivers to maintain directional control, maximizing acceleration and optimizing elapsed time.