1964–67 Chevelle, GTO & GM A-body chassis stiffening
2 kits to stiffen the frame, from frame rails and connectors to braces and roll bars.
- How it's built
- Body-on-frame perimeter frame: boxed front section, open C-channel center and rear rails (convertibles used a stronger boxed frame)
- Weak spots
- The open C-channel center and rear rails twist, and the rear control-arm frame mounts crack under traction. Rubber body mounts, poor camber gain and bump steer limit handling.
Stiffening kits
| Area | Kit | What it is | Price |
|---|---|---|---|
| Frame stiffening | UMI Performance 4029 Rear Control Arm Reinforcements/Frame Braces | DOM braces tie the rear arm mounts to the frame to stop cracking | $159.99 pair Source |
| Frame stiffening | ABC Performance 1964-1967 GM A-Body Frame Boxing / Stiffening Kit | CNC 1/8 in. plates box the open center and rear rails; may need a tubular trans crossmember | $354.99 Pro Touring Store price; weld-in Source |
Prices are from the linked seller pages and change often. Confirm fitment for your exact year and body style before ordering; many weld-in parts need professional installation. Some links earn us a commission.
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