1964½–70 Mustang chassis stiffening
8 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 (front subframe) and short rear frame rails
- Weak spots
- Front and rear rails are not tied together, so the floor and rockers flex and the shock towers crack. High roll-center geometry, spring loads in the towers, and vague linkage-assist steering limit grip and feel.
Stiffening kits
| Area | Kit | What it is | Price |
|---|---|---|---|
| Subframe connectors | Scott Drake Black Subframe Connectors Mustang Coupe/Fastback 64.5-70 (C5ZZ5479A) | Listed on CJ Pony Parts subframe connector category. | $214.95 CJ Pony Parts category listing price Source |
| Subframe connectors | Detroit Speed Subframe Connectors 010105DS | Weld-in; attaches to DSE torque boxes. | $307.95 DSE list price Source |
| Subframe connectors | Total Control Products Subframe Connectors Weld-On Pair Coupe/Fastback 65-70 (SUBFC-01) | Weld-in; powder coat must be ground off at welds. | $409.99 CJ Pony Parts price Source |
| Torque boxes | Detroit Speed Rear Torque Box Kit - Stock Suspension 010109DS | Rear torque boxes for stock leaf suspension; mates to 010105 connectors. | $252.95 DSE list price Source |
| Frame stiffening | Detroit Speed Subframe Connectors 010105DS (64-70 Mustang) | Weld-in 1.5x2.5in tube connectors that tie the front subframe to the rear rails | $292.95 DSE list price Source |
| Frame stiffening | Total Control Products Adjustable Aluminum Shock Tower Brace kit TWRB (65-70) | Tower export brace, Monte Carlo bar and truss braces tie the towers to the firewall | $610.99 CJ Pony sale price (MSRP $628.99) Source |
| Shock & strut tower braces | Global West 1967-70 Ford Mustang Tubular Export Braces | Tubular shock-tower-to-firewall braces. | $374.99 Classic Industries category listing price Source |
| Shock & strut tower braces | Global West Chassis Stiffening Kit Coupe/Fastback 1967-1970 (CSK1) | Weld-in subframe connectors plus adjustable tubular export brace and Monte Carlo bar. | $801.97 CJ Pony Parts price 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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