1967–76 Mopar A-body (Dart, Duster, Barracuda, Valiant) chassis stiffening
7 kits to stiffen the body shell, from frame rails and connectors to braces and roll bars.
- How it's built
- Unibody with welded-in front frame rails and a bolt-in K-member
- Weak spots
- Front and rear rails are not connected, so the body twists, and the K-member can crack around the steering box. The stock box has a slow, numb ratio and the leafs allow axle wrap.
Stiffening kits
| Area | Kit | What it is | Price |
|---|---|---|---|
| Subframe connectors | Hotchkis 4014 Subframe Connector Kit, 108in Wheelbase | Duster, Demon, Valiant, Barracuda (108 in WB). | $399.99 Hotchkis list price Source |
| Subframe connectors | Hotchkis 4015 Subframe Connector Kit, 111in Wheelbase | Dart, Scamp, later Valiant (111 in WB). | $399.99 Hotchkis list price Source |
| Subframe connectors | US Car Tool Level 1 Chassis Stiffening Kit 67-75 Dart/Valiant (USC1M1015) | Weld-in connectors plus four torque boxes; not for Duster. | $693.99 Mancini Racing price Source |
| Torque boxes | US Car Tool Torque Boxes Set (2) Rear 1967-75 A-Body (USC1M1515) | Weld-in rear torque boxes. | $211.99 Mancini Racing price Source |
| Torque boxes | Not stated (Mancini Racing listing) Torque Boxes Front, set of two, 1967-75 A-Body (USC1M1514) | Front torque box pair. | $211.99 Mancini Racing price Source |
| Frame stiffening | Firm Feel K-Frame Reinforcement Kit ('62-'76, DIY) | Weld-on plates and skid plate to stop K-member cracking | $100 Firm Feel list Source |
| Frame stiffening | Hotchkis Subframe Connector Kit 4014 (108in wheelbase A-body) | Ties front and rear rails together to reduce flex | $399.99 Hotchkis list 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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