A-Arm 8.5in Screw-In B/J

The A-Arm 8.5in Screw-In B/J from JOES RACING PRODUCTS is a precision tubular upper control arm engineered for serious suspension geometry work on high-performance and modified vehicles. This component is built for enthusiasts and fabricators who demand adjustability and durability when tuning front-end alignment, caster, and camber settings. Whether you're building a road race platform, preparing for autocross competition, or executing a custom suspension overhaul, this screw-in ball joint design allows micro-adjustments that stamped arms simply cannot deliver.

Manufactured from aluminum and steel construction with a durable black powder-coat finish, the A-Arm 8.5in Screw-In B/J features a 10-degree geometry and a screw-in ball joint that enables length adjustment without disassembly. The tubular design minimizes mass while maximizing rigidity—critical for maintaining consistent suspension compliance under sustained cornering loads. The 8.5-inch length and standard bushing style make this arm compatible with numerous chassis platforms, and the screw-in ball joint mechanism is the industry standard for drift, circuit, and off-road racing where geometry precision directly impacts tire wear, handling response, and driver feedback.

Mechanics and fabricators building custom or competition-oriented suspension systems will find this upper control arm invaluable for dialing in front-end geometry on modified chassis. Installation requires proper alignment equipment and understanding of suspension geometry—this is a component for users who comprehend the relationship between caster, camber, and vehicle dynamics. Sold individually, you will need one per side for a complete upper control arm replacement, making it essential to source matching pairs for symmetrical geometry and predictable handling characteristics.