QA1 R370-110 HD Pro Rear Drag 4-Link System with MOD Shocks and 110lb Springs

The QA1 R370-110 HD Pro Rear Drag 4-Link System is a complete, all-in-one rear suspension solution engineered for serious drag racers who demand professional-grade performance without compromise. This kit streamlines the custom fabrication process by bundling every component needed to build a race-proven 4-link rear suspension from a single source.

At the heart of the system are QA1's MOD Series 4-Way Adjustable Coilover Shocks paired with 110 lb/in linear-rate springs. The MOD Series shocks utilize QuickTune Technology — dry modular valve packs that can be swapped in minutes without removing the shocks from the vehicle, preserving your nitrogen charge and oil integrity throughout. Independent compression and rebound adjustment delivers an expansive force curve for precise tuning to changing track conditions. All QA1 shocks are 100% dyno-tested and serialized.

The heavy-duty structural components are built to withstand the rigors of high-horsepower drag racing. ¼-inch-thick mounting plates, 1-1/4-inch trailing arm tubes, Grade 8 hardware, and QA1 chromoly rod ends provide maximum strength and minimal deflection for consistent power transfer. The kit offers a wide range of instant center tuning and on-car adjustability, and all tubular components can be cut to length to fit virtually any chassis with 40-inch or narrower frame rails.

Kit Contents:

• 22" trailing arm tubes, brackets, rod ends, and tube adapters
• 40" shock crossmember with mounting tabs
• 40" diagonal link kit with mounting brackets (for lateral axle location)
• Grade 8 hardware kit
• MOD Series 4-Way Adjustable Coilover Shocks (pair)
• 110 lb/in linear-rate coilover springs (pair)

Fitment Notes:

• Welding required for installation
• Trailing arm tubes and diagonal links can be cut to length
• Compatible with 3-inch axle tubes
• Works with 40-inch and narrower frame rails

Made in the USA at QA1's facility in Lakeville, Minnesota, the R370-110 is backed by QA1's best-in-class warranty. Register at QA1.net/warranty for lifetime shock coverage.