MZ UPPER CONTROL ARMS

Upper Control Arms 101

  • All of our arms are fabricated using 3/16” steel plate and 1/4” thick pivot cups. The industry standard is thin 1/8” bent tubing.
  • We use CNC machined 1/4” thick crush sleeves for maximum surface area on the inner pivot plates so that the arm holds a locked position and alignment dimensions stay tight. The industry standard is bandsaw cut 1/8” tubing. 
  • We use CNC machined high density thermoplastic (Delrin) inner bushing material for strength and longevity. A rigid bushing is ideal to keep unwanted dimensional movement to a minimum while being exposed in a high heat environment next to the engine and exhaust. The industry standard is cheap polyurethane. 
  • One of the most important parts on our arm is our one piece CNC machined 17-4 heat treated stainless steel taper pins that connect the uniball to the spindle upright. We have tested a most commonly used through bolt design that creates tolerance stacking in the joint and also lets moisture in between the dissimilar metals which creates electrolysis and corrosion that ultimately leads to failure. 
  • We opt to use an open uniball instead of a ball joint purely for its strength characteristics. Some companies use a cap over the top of the uniball to insist that it is sealed but in reality moisture can still get in the bearing from the bottom and the cap just holds moisture in from the top. Uniballs need to be clean and dry for optimal performance. 
  • We add additional pivot geometry dimensions to achieve greater alignment parameters for many lifted or long travel applications. These changes are made in the length of the arm, increased caster adjustment, and outer pivot height above the spindle upright.