Torsion Bar Suspension

cars · engineering · suspension systems

Metal bar spring. Instead of bouncing springs, some cars use a long metal bar attached to the chassis that twists and untwists when the wheel hits a bump, making the ride smoother.

How it twists. One end of the bar stays locked to the car's frame, while the other end connects to a lever called a torsion key that moves with the wheel, causing the bar to rotate around its center.

Customizable stiffness. The bar's springiness depends on how long it is, what shape it has, what metal it's made from, and how it was manufactured, so engineers can tune each car's suspension perfectly.

Smooth ride. When your wheel bounces up and down, the torsion bar resists that motion by twisting, which absorbs the impact and keeps the car from jolting around.