UMI*s bolt-in rear coilover kit allows full ride height, spring rate and damping adjustments, while trailing arm adjustment enables fine tuning of instant center. The reinforced upper mount is a direct bolt-in (requiring one additional hole to be drilled) and holds a true 2-1/2* racing coilover with double-shear mount. The FEA designed reinforced lower brackets bolt directly over the stock rear lower control arm mounts, utilizing the existing lower shock hole(s) (may requiring drilling of additional hole depending on factory configuration). The 2-hole trailing arm height adjustment enables fine tuning of instant center location for drag launch or auto-x/road race rear steer tuning. The Viking Performance shock is 19-way adjustable in both compression and rebound, and ensures the perfect setting for every application. The 2-1/2* coilover springs are available in 12* 175lb for drag use, 12* 225lb for street use and 12* 250lb for auto-x/road race. 100% designed, manufactured and raced out of Philipsburg, PA-USA and always US materials.