QA1 52621-D600 Front Coilover Conversion System Double Adjustable 600 lb/in Springs 5-7in Drop

The QA1 52621-D600 is a complete front coilover conversion system engineered from the ground up as a modern suspension solution for 1965–1979 Ford F-100 trucks, covering both bump-side and dent-side generations. This kit replaces the factory front suspension with a purpose-built performance system designed for superior handling, an aggressive lowered stance, and significant weight reduction.

This double adjustable version features 600 lb/in coilover springs and provides an adjustable ride height drop range of 5 to 7 inches using the included drop spindles, or 3 to 5 inches with standard spindles. The front-end geometry is 3.75 inches narrower than a typical Crown Victoria swap, allowing fitment of wider wheels and tires while improving cornering stability. The system also sheds approximately 150 lbs from the front end compared to factory components, resulting in improved responsiveness and handling balance.

Kit Includes:

• Double adjustable coilover shocks (rebound and compression independently tunable)
• 600 lb/in coilover springs
• Tubular steel control arms — black powder coat finish
• Mounting brackets and hardware
• Drop spindles (1979–1981 Camaro-sourced; front brakes must match)
• Fox Body Mustang-based rack and pinion steering unit
• U-bolt kit
• Inner fender trimming template

Key Specifications:

• Shock Adjustability: Double adjustable (independent rebound and compression)
• Spring Rate: 600 lbs/in
• Drop Range: 5–7 inches (with included drop spindles); 3–5 inches (with standard spindles)
• Construction: Steel, black powder coat
• Steering Rack: Fox Body Mustang-based, 9/16"-18 pressure port / 5/8"-18 return (requires -6 AN adapter fittings and custom hoses)
• Sold as a complete kit (engine mounts not included)

Installation Notes:

• Spindles are sourced from a 1979–1981 Camaro; front brake components must be matched accordingly
• Inner fender trimming is required; an easy-to-use template is included
• A Borgeson 3/4-36 x 3/4 DD steering connection (Part #013449) or equivalent is recommended at the rack
• Some engine/header combinations may require up to three steering U-joints
• Custom power steering line routing and adapter fittings are required

The QA1 52621-D600 is the ideal choice for builders seeking a complete, bolt-in front suspension overhaul that delivers a modern driving experience, lower stance, and serious performance gains — without cobbling together parts from multiple donor vehicles.