QA1 GD508-10550C GM Pro-Coil Front Double Adjustable Coilover Shock Kit 550lb 10in Spring

The QA1 GD508-10550C is a front Pro-Coil double adjustable coilover shock kit engineered for GM applications. Featuring a lightweight billet aluminum shock body, this bolt-in system replaces your factory front shocks and springs with a fully adjustable coilover setup that delivers superior ride height control and precision valving tuning — all while retaining stock-location control arms.

The double adjustable design provides truly independent compression and rebound adjustment, with 18 positions of rebound and 18 positions of compression, yielding 324 distinct valving combinations. This allows fine-tuned suspension tuning for any driving condition, from daily street use to competitive motorsport applications. The fully threaded aluminum shock body provides up to 2 inches of ride height adjustment for dialing in the perfect stance or optimizing weight balance.

Included is a 10-inch tapered flat (large) spring rated at 550 lb/in, with a shock compressed length of 9.63 inches and an extended length of 14.50 inches. The American-made high-travel springs feature fewer coils and a smaller wire diameter compared to standard springs, reducing unsprung weight and improving suspension response. Each unit is 100% dyno tested and serialized at the factory, and is fully serviceable and rebuildable through QA1 Authorized Service Centers.

Key Features:

• Double adjustable: 18 compression + 18 rebound positions (324 total valving combinations)
• Lightweight billet aluminum coilover shock body
• Compressed length: 9.63" | Extended length: 14.50"
• Includes 10-inch tapered flat spring, 550 lb/in rate
• Fully threaded body — up to 2" of ride height adjustment
• Stock upper stud mount and T-bar lower mount
• High-travel spring design reduces unsprung weight for faster suspension response
• 100% dyno tested and serialized
• Serviceable and rebuildable by QA1 Authorized Service Centers
• Bolt-in installation — no modification to factory control arms required
• Also available in Single Adjustable and Drag Race "R" Series configurations
• Proudly made in the USA
• Sold in pairs

The QA1 GD508-10550C Pro-Coil coilover system is an ideal suspension upgrade for muscle cars, classic trucks, and performance builds demanding precise, driver-adjustable damping without sacrificing a stock-like installation footprint.