The purpose of the panhard rod/track bar is to locate the rear axle along the centerline of the chassis. The current chassis manufactuers right side mounting bracket has a series of vertical holes so that the bar can be unbolted and moved up or down as required and then rebolted. Adjusting the right side track bar end upward moves the rear axle to the right, and therefore both rear tires. Adjusting it downward moves the rear axle to the left, and therefore both rear tires. Raising the track bar makes the car looser (oversteer) and lowering the track bar makes the car tighter (understeer).
In a turn, a car transfers weight from the inside of the car to the outside of the car due to centrifugal force. On an oval track that means more weight moves from the left side to the right side in a turn. When the rear axle is moved to the right, more weight is moved to the left of the centerline. This allows more weight to transfer during cornering (more body roll). The opposite is true if the rear axle is shifted to the left, more weight is then moved to the right of the centerline and less weight is available for weight transfer to the right side during cornering (less body roll). In conjunction with all this and because of the trailing arm geometry on quarter midgets, moving the axle to the right shortens the right side wheel base, which results in loosening the car (oversteer) and shifting the axle to the left lengthens the right side wheel base, which results in tightening the car (understeer). Now that we understand that adjusting the track bar shifts the rear end right or left and also creates rear stear, it is easy to imagine the affect on the cars handling.
CA Residents: WARNING: Cancer and Reproductive Harm www.P65Warnings.ca.gov
