As racers, we constantly make adjustments to our driving style, car preferences, engine, and most of all, suspension. Factory engineers do not stress test components to the abuse seen in motorsport, which leaves a niche for aftermarket manufacturers to fill. It's a given that having major suspension components such as upgraded coilovers will enhance your vehicle's performance, but too often we disregard the rest. Having a fully-adjustable and compliant suspension does not just mean having coilovers, but upgraded control arms and links as well.
Control arms are one of the most important elements of your vehicle’s suspension, as they hold in the knuckles, spindles, and axles to your car while allowing up and down articulation of your suspension. Included with a control arm assembly are ball joints and rubber bushings pressed securely, which serve as the primary mounting point for the arms. Aftermarket adjustable control arms, paired with spherical bushings allow one to achieve specific alignment settings not possible with stock parts, and are often needed to work hand in hand with your lowering arrangements.
For example, if you were to purely lower your car, your alignment settings will inevitably change. This can mean unregulated camber increases on all 4 corners, which factory components may not remedy even with an alignment. Negative effects such as incorrect pinion angle, can increase wear and tear on seals and drive-train components, while depriving tires of proper traction and wear patterns needed for road and track driving.
Most cars come equipped with front and rear control arms, and are most likely not adjustable. Limited adjustment is due to cars expected to be aligned to factory spec, not to offer the extra adjustment you need for your performance needs. Adjustable length control arms, on the other hand, can allow you a much wider variety of alignment settings to achieve your desired handling characteristics out of your car. These make adjustable length control arms a must when lowering your car, as even through alignment, it may be impossible to revert the car to even factory spec and beyond. Moreover, alignment jobs become much more efficient, with jam nuts or clamps to lock in one's desired specifications. Most adjustable arms are CNC-machined and TIG-welded for maximum strength; proving the overall better and safer option than the OEM assembly.
The ideal adjustable control arm or link assembly will utilize a spherical end, contrary to the big rubber bushings inherent to factory parts. This allows the control arm to move much more freely in all directions, while eliminating possible suspension binding which can cause spontaneous loading and unloading of the car. Spherical bushings also allow for correct alignment settings to be held throughout hard cornering, whereas rubber bushings would deflect and therefore lead to unpredictability in the car mid-turn, which can lead to dangerous scenarios.
Furthermore, factory rubber bushings can tear and deteriorate over time, which can prove unsafe even in road-going conditions. The soft-compound nature of rubber bushings lead to deformity through load, which can hamper your alignment settings as your arm is not held in place correctly. Replacing said bushings can not only be a difficult task, but can put your factory arm at risk due to the needed force and pressure to press out the OEM bushings.
Spherical bushings are not only the safer and stronger option, but self-clean and self-lubricate due to their Teflon lining while not needed to be replaced. As a result, allowing them to be more consistent for track use, as opposed to inconsistent and easily deforming rubber bushings. In conclusion, the integration of an adjustable control arm for your vehicle proves to not only enhance your car’s handling characteristics, but is a necessary modification for those looking to harmonize their vehicle’s suspension components through endless adjustability.