QA1 DD501-12300 HD Pro Rear Coilover Conversion System 3.0" Double Adjustable 300lb

The QA1 DD501-12300 HD Pro Rear Coilover Conversion System is a heavy-duty rear suspension upgrade designed for racers and performance enthusiasts who demand precise, tunable damping control. Engineered around a 3.0" axle tube diameter, this system allows you to convert a traditional leaf spring or solid axle rear suspension to a fully adjustable coilover setup — unlocking significantly improved handling, ride height adjustment, and on-the-fly tuning capability.

At the heart of this kit are two double adjustable coilover shocks, giving you independent control over both compression and rebound damping. Paired with 300 lb/in rate springs and a 40" weld-in tube, this kit provides everything needed to build a robust, competition-ready rear suspension foundation.

Key Features:

• Double adjustable shocks — independent compression and rebound damping adjustment for precise suspension tuning
• 300 lb/in spring rate — suited for performance street and track applications
• 3.0" axle tube diameter compatibility
• 40" weld-in tube included for structural integration
• Comes complete with two coilover shocks, two springs, and all required mounting hardware
• HD Pro (Heavy Duty Pro) construction for high-stress racing and performance environments
• Allows ride height adjustment via threaded spring perch collars

The QA1 HD Pro Rear Coilover Conversion System is a professional-grade solution for custom chassis builders, drag racers, oval track competitors, and serious performance builders looking to maximize the rear suspension's tunability and consistency.