QA1 DS501-1501 Pro Rear Weld-In Coilover Conversion Kit Single Adjustable Proma Star 150lb/in 3.25in Axle

The QA1 DS501-1501 is a complete Pro Rear weld-in coilover conversion kit featuring single adjustable Proma Star shocks and 150 lb/in linear rate springs, designed for 3.25-inch diameter rear axle tubes. This bolt-in coilover system is a popular choice for drag racing, street performance, and street rod builds where ride height adjustability and tunable damping are essential.

The single adjustable Proma Star DS501 shocks simultaneously adjust compression and rebound damping, allowing you to dial in the ideal balance between comfort and performance with a simple turn of a dial. Valving changes are evenly spaced throughout the adjustment range, ensuring smooth transitions between clicks with no abrupt jumps in feel.

Kit Contents:

• (2) Single adjustable Proma Star DS501 coilover shocks — 100% dyno tested and serialized
• (2) 12 in. linear rate 12HT150 springs (150 lb/in. rate)
• 1.625 in. O.D. x 0.095 in. wall x 40 in. long weld-in upper shock mount tube
• Axle mount brackets and all necessary mounting hardware

Key Features:

• Simultaneous compression and rebound single adjustable (DS) valving
• Lightweight aluminum construction — ride height adjustable
• Precision machined aluminum piston with PTFE piston band
• 5/8 in. centerless ground, hard chrome plated solid piston rod
• Three-step sealing system for long-term durability
• Revalveable and rebuildable by QA1 factory or authorized service centers
• Designed for 3.25 in. diameter axle tubes
• Note: Welding required for installation; QA1 spanner wrench T114W or T115W recommended
• Made in the USA

The axle-mounted brackets provide ride height adjustment in ¾ in. increments, and the coilover shock itself allows additional fine-tuning, delivering up to 9 inches of total ride height adjustability. QA1 backs this kit with a best-in-class limited lifetime warranty on the shocks when registered at QA1.net/Warranty.