Body tuning involves adding or modifying spoilers and a body kit in order to improve the aerodynamic performance of a vehicle. Through the generation of downforce, cornering speeds and tire adhesion can be improved, often at the expense of increased drag. To lighten the vehicle, bodywork components such as hoods and rear view mirrors may be replaced with lighter weight components.
Often, body modifications are done mainly to improve a vehicle’s appearance, as in the case of non-functioning scoops, wide arches or other aesthetic modification. Aftermarket spoilers or body kits rarely improve a car’s performance. The majority, in fact, add weight and increase the drag coefficient of the vehicle, thus reducing its overall performance.
Increasing the wheel track width through spacers and wide body kits enhance the cars cornering ability. Lowering the center of gravity via suspension modifications is another aim of body tuning. Often, suspension tuners unfamiliar with spring dynamics will cut stock springs, producing a harder, bouncy ride. It is also common to lower the car too far, beyond the optimal height for performance, purely for appearance.
Competition cars may have light weight windows, or the windows may be completely removed, as auto glass adds significant weight high up. Plastic windows are much more vulnerable to scratches which reduces service life.