The Skinny on Swaybars

I don’t get how swaybars work. It looks as if they just go up and down with the suspension arms. How does that do anything?

If the left and right suspension arms are both going up and down together (as they do when landing off a jump, for example), then you’re right—the swaybar is just along for the ride. Swaybars (or more accurately, anti-swaybars) do their thing when the car is cornering. During a turn, the chassis rolls or sways to the outside of the turn, causing the outboard suspension arm to move up and the inboard arm to move down, relative to the chassis. The swaybar is designed to reduce this effect and help the chassis stay flatter in turns, hence the term “anti-swaybar” or “anti-roll bar.” The swaybar is made out of spring steel, which allows the suspension to remain independent. The amount of flex in the swaybar is determined by its thickness (thicker = stiffer) and how close the “arms” of the swaybar are to the part of the bar that twists under load (shorter = stiffer).

Shown here on a Pro-line PRO-2 SC, the swaybar transfers some of the load applied to one side of the suspension to the other, helping keep the chassis flat. Cornering forces cause the chassis to sway or roll to the outside of the turn. Swaybars reduce this effect.