UMI Performance 3057-1-B Lower A-Arm Control Arm with Adjustable Steering Stop

The UMI Performance 3057-1-B lower A-arm is a high-performance suspension control arm engineered for GM muscle cars and street machines. Designed for serious enthusiasts who demand superior handling in road racing, autocross, drag racing, and aggressive street driving, these arms deliver competition-grade performance with American-made quality.

Key Features:

• CNC laser-cut components with 1-¼" and 1-½" USA DOM tubing construction for maximum strength and precision
• Relocated ball joint cup offers 10 degrees of caster when paired with UMI 3056 upper A-arms while maintaining centered spindle pin geometry
• ¾" taller Howe ball joint optimizes roll center, lowers center of gravity, and reduces ride height by ½"
• Removable double shear shock mount allows spring and shock changes without disconnecting ball joints—ideal for trackside adjustments
• UMI-designed and machined Delrin bushings provide smooth, bind-free articulation throughout suspension travel
• Adjustable aluminum steering stop prevents tire and wheel contact at full lock
• Double shear swivel sway bar mounts accept UMI 3035 and most factory eyelet-style aftermarket sway bars
• Shock mount spacing compatible with Afco, Viking, Ridetech, and other aftermarket shock and spring combinations
• Weighs 3.2 lbs less per pair compared to factory stamped steel A-arms
• Available in UMI red or black powder coat finish

Designed, tested, manufactured, and raced in Philipsburg, Pennsylvania, the 3057-1-B lower A-arms have been battle-tested on UMI's iconic Green Machine. For optimal performance, UMI recommends pairing these lower arms with caster-corrected upper A-arms and adding the 3060 bump steer kit. Built for racers by racers, these arms deliver the durability and adjustability needed for serious performance applications.