UMI PERFORMANCE
UMI Performance 64-72 GM A-Body Rear Coilover Kit Control Arm Relocation Bolt In
SKU: U01C 4057
Description
Part #: 4057
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. 100% designed, manufactured and raced out of Philipsburg, PA-USA and always US materials.
Fitment
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Specifications
| Brand | UMI PERFORMANCE |
| Part Number | U01C 4057 |
Buy with Confidence
Built for enthusiasts. Every order is backed by our 30 day return window on eligible items. Unused and uninstalled products may be returned with approved RMA and no restocking fees when received in new condition. Orders placed through the MOTORMIA app with a complete build qualify for our Fitment Guarantee — free return shipping if the part doesn’t fit your exact setup. The guarantee covers fit only; installation must follow manufacturer instructions, and we recommend a qualified shop for parts marked Difficulty 4–5.
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