BMR 11-14 S197 Mustang Upper Control Arm On-Car Adj. (Polyurethane) - RedCombine this with soft bushings that have massive amounts of deflection and youre left with poor performance. The UTCA034s heavy duty construction eliminates control arm flex, giving you much improved repeatability on the street, starting line, or in the corners. BMRs polyurethane bushings are designed to be compliant enough to give you a comfortable ride and absorb NVH, while remaining firm enough to stand up to high loads of any performance