UMI Performance’s 12-bolt swap control arms are designed to bolt a 1964-1972 GM A-Body 10-Bolt or 12-Bolt rear end into a 1978-1988 GM G-Body; this includes Monte Carlo, Malibu, El Camino, Regal, Grand National, Grand Prix and Cutlass. These upper control arms are built at the correct angle to attach to the G-Body chassis as well as the A-Body rear end “ears”. These upper control arms are a must any time this swap is being completed. Using the factory control arms will cause drastic rear end bind and incorrect driveline angle, this leads to traction lose, vibrations and unsafe handling.
These control arms are supplied adjustable for easy on car adjustability to set correct pinion angle and allow adjustment for installation if needed. Adjustments are made using an aircraft quality 4140 chrome moly heat treated adjuster and UMI spherical Roto-Joint’s. The Roto-Joint allows rear end free movement when high handling, auto cross or road race is a concern but also works excellent as a drag race item by eliminating rear end bind. Upper control arms feature TIG welded construction, 4140 chrome moly tube adaptors to insure thread durability and brilliant powder coat.
- On car adjustable
- Mounting plate CNC machined from 0.250” thick mild steel
- 4140 heat treated chrome moly adjuster
- 4140 chrome moly threaded tube adaptors
- Spherical Roto-Joints installed
- Shipped fully assembled and ready to install
- Uses OEM hardware
- Brilliant and durable powder coat finish
More about Roto-Joint Technology….. UMI’s Roto-Joint, short for Rotational Joint, allows 28 degrees of total rotation and unrestricted movement throughout the vehicles suspension. The Roto-Joint is designed to work like a spherical rod end while maintaining streetable qualities of a softer bushing. The Roto-Joint is designed to articulate and prevent suspension bind, and since the installed delrin race does not deflect like softer bushings, there is an improvement in traction and a significant reduction in wheel hop. The construction of the Roto-Joint features a 4140 chrome moly, hard chrome plated spherical ball which rotates in a delrin race. The 4140 chrome moly material and hard chrome plating are designed for extensive wear resistance against hard driving and accumulated miles. The spherical ball rotates in the CNC machined delrin bushing, which is contoured for the spherical ball to allow unrestricted movement as the ball rotates. Delrin is the bushing material of choice due to its high resistance against wear, great tensile strength, and ability to maintain its physical properties. The housing of the Roto-Joint features 4140 chrome moly threads, and a CNC machined bushing holder TIG welded together for the utmost in strength and durability. The UMI Roto-Joint is adjustable and 100% rebuildable. This means as the delrin race wears the adjuster ring can be tightened using the optional spanner wrench to apply tension to the ball. If the delrin race would ever wear completely it can be replaced easily.
Spanner Wrench- This spanner wrenched is used for adjusting and disassembling Roto-Joints used in all UMI Performance products. Over time if the delrin race inside the Roto-Joint would wear the spanner wrench is used to tighten the adjusting ring applying more pressure to the delrin inside. The spanner wrench is also used to disassemble the Roto-Joint for cleaning, inspection and rebuilding.