Mopar torsion bars are preset at the factory in the direction of use. You can observe this preset by laying the bars down on a flat surface and observing how the bar is twisted. The driver’s side bars will have a 30 degree right hand twist. A passenger side bar will have a 30 degree left handed twist. Pre-setting the bars in this manner improves the load carrying capacity in the pre-set direction. But, the load carrying capacity is reduced in the other direction of twist. This is why it is so important to get the bars installed on the correct side of the car. This twist is put into the bar during fabrication and is done to strengthen the bar. If the bars are put on the wrong side, they will be loaded against the pre-set and will not be able to carry their rated load.
