QA1 RCK52377 Rear Pro-Coil Single-Adjustable Coilover Conversion Kit for 1973-1977 GM A-Body

The QA1 RCK52377 is a bolt-in rear coilover conversion kit designed for 1973–1977 GM A-Body vehicles including the Chevelle, El Camino, and Monte Carlo. This complete Pro-Coil System replaces the factory rear suspension with a fully adjustable coilover setup — no cutting or welding required.

At the heart of this kit are two single-adjustable Proma Star aluminum shocks featuring a fully threaded body that allows precise ride height tuning. With 18 positions of simultaneous rebound and compression adjustment, you can dial in the perfect balance of ride comfort and performance handling for street or occasional track use. The threaded shock body enables ride height adjustment ranging from 1" higher than stock down to 3" lower than stock.

The included high-travel springs are purpose-built for QA1's Pro Coil Systems. Their lightweight design features fewer coils and a smaller wire diameter, resulting in increased suspension travel and faster response. This reduces unsprung weight and improves overall suspension performance compared to standard coil springs.

Kit Includes:

• (2) Single-adjustable Proma Star aluminum shocks
• (2) High-travel coil springs — 12 in. length, 200 lb/in. spring rate
• USA-made mounting brackets
• All necessary hardware for complete installation

Key Features:

• Bolt-in installation — no cutting or welding required
• Fully threaded aluminum shock body for ride height adjustment
• 18-position simultaneous rebound and compression damping adjustment
• 100% dyno tested and serialized
• Rebuildable and re-valveable by QA1 factory or authorized service centers
• Proudly made in the USA in Lakeville, Minnesota
• Eligible for QA1's Limited Lifetime Warranty (registration required at QA1.net/Warranty)

Note: Lower shock mount bracket may not be compatible with aftermarket rear end housings. This kit will lower the vehicle — take vehicle weight into account when selecting spring rates.