As you drive your car undergoes stress as your whole chassis will twist and absorb a lot of energy created by the force of inertia and gravity. Over the years, it s been proven that a performance vehicle must reinforce the chassis and make a more rigid frame by connecting points in your vehicle that are crucial to the behavior of your vehicle. By connecting points in your chassis and reinforcing the frame you are able to channel that energy that is being absorbed by the chassis flex back into your suspension components. This allows your suspension components such as your springs, shocks, and swaybars to do their job more effectively with more stability. The C-Pillar in the rear is the highest point into which you can brace your vehicle and the point into which the chassis flexes the most. Because of this, the C-Pillar takes in quite amount of stress that the C-Pillar Brace can take in and make a noticable effect on the stability of the vehicle, mainly the rear.