6. The Detroit Speed Inc. lower control arms (PN 031201) are tubular works of art. To make life easier, they ship complete with lower ball joints, steering stops, jounce bumpers installed, and are ready to rock. Performance features include thick-wall tubular construction with gussets and crossbracing for added strength. The bushings are Delrin with steel housings and crush tubes. Since we were keeping it simple, these were designed for traditional coil springs, but they also come set up for coilovers.