The single upper control arm is responsible for maintaining pinion angle and preventing axle counter-rotation. This "3 link" style suspension is ideal for autocross and road race applications as it allows the most articulation possible with a solid axle. For drag racing, however, the single, centered link becomes a weak point as the arm is only one inch thick in the middle and made from light gauge, stamped steel. Our upper control arm is made from 1 5/8" .120 wall DOM tube and is MIG welded.