Detroit Speed’s front subframe for 1967-69 GM F-Body and 1968-74 X-Body vehicles is a no-compromise, bolt-in replacement engineered for modern handling, structural strength, and versatile engine support. As the only subframe in the aftermarket with hydroformed frame rails, its sculpted design offers exceptional stiffness and mirrors the factory contours for a seamless fit and appearance that looks and feels like a purpose-built upgrade. Whether you’re building a street cruiser or track machine, this subframe blends OEM-level engineering with race-proven performance. Designed for SBC, BBC, and LS engines, it features Detroit Speed’s exclusive geometry, stamped crossmembers, and clearance for wide wheels—all built for grip, steering precision, and durability.

PERFORMANCE RIDE & HANDLING

Detroit Speed’s proprietary suspension geometry delivers superior cornering grip and high-speed stability. Paired with the ‘Detroit Tuned’ shocks co-developed with JRi, this package offers responsive, predictable performance with a ride quality that doesn’t punish you on the street.

HYDROFORMED RAIL TECHNOLOGY

Detroit Speed is the only aftermarket manufacturer using hydroformed steel rails in its subframe—a low-temp process that retains strength and dimensional accuracy. This results in superior rigidity and consistent structural integrity under load. The precision-fit installation requires no fender massaging and leaves the engine bay clean and uncluttered.

FLEX-FREE CHASSIS INTEGRITY

Stamped main and secondary crossmembers reinforce the subframe to reduce flex and improve steering response. The added rigidity ensures consistent geometry retention under hard braking and cornering.

ENGINE SWAP READY

Designed to accept SBC, BBC, and LS engines without modification, this subframe gives builders the flexibility to accommodate modern or legacy drivetrains with ease.

WIDE TIRE COMPATIBILITY

Optimized geometry and smart packaging allow clearance for 10” wide wheels with no inner wheel well mods—giving you aggressive grip and stance with no added fabrication.

FEATURES & BENEFITS

• Hydroformed rails preserve material strength and add torsional rigidity
• ‘Detroit Tuned’ JRi shocks deliver race-inspired damping for refined street performance
• Stamped structural crossmembers reduce flex and improve chassis feedback
• Designed to accept multiple GM engine platforms with no cutting or welding
• Rack-and-pinion geometry optimized for precise and responsive steering
• Provides aggressive stance and grip without requiring wheel tub modifications
• Fully bolt-in installation with OE-style mounting points
• Made in the USA with industry-leading quality and engineering

OPTIONS

• Coil-over shocks: Non-Adjustable, Single Adjustable, Double Adjustable, or Remote Reservoir Double Adjustable
• Spring rates: 550 lb/in (Small Block/LS/LT) or 650 lb/in (Big Block)
• Finish: Powder Coated or Bare Steel

FITMENT NOTES

• Requires minimum 17” wheel diameter with at least 16.25” of inside barrel clearance
• Optional fluid transfer kit available for AN-converted rack & pinion plumbing
• Ships via freight