Books have been written illustrating the math, science and design of suspension systems. The time, money and experience compiling these books is almost immeasurable. The benefit of all this, to the enthusiast is the compilation of some finite qualifications that aid in the selection of suspension components. In the case of coil-overs, buyers should consider a handful of variables: price, application, construction and adjustment capabilities.

Price Application

Coil-over suspension prices vary as much as the available configurations. Just like anything else, the most expensive system does not guarantee the best performance for every application. These suspension systems are available for applications ranging from show to full-on racing. That being said, the most expensive and capable system may not be the logical choice for everyone. It may feature adjustability that will never be utilized. Think of using a sledge hammer to pound in a nail. It'll get the job done, but it's a bit much. For the people driving everyday on the street and tracking on the weekends, the entry-level coilovers make the most sense, while a purpose-built racecar will need every point of adjustability to allow the driver to squeeze every fraction of a second out of a track.

Top Down Design

The hat or the top portion of a coilover is a good place to start looking when considering a coil-over system. Many systems include a camber plate and pillow mount designed to replace the factory hat. The pillow mount provides a more rigid interface between the suspension and the frame. The benefit is greater predictability and more direct feedback from the suspension to the driver. Adjustable camber plates allow for adjustment of the camber without the need for any additional parts.

Springs 'N' Things

Further down the coilover assembly is none other than the coil itself. As mentioned before the coil is designed to hold the weight of the car, but this is not its only job. The coil is also responsible for keeping the tire firmly planted on the ground through bumps and changes in the road. This means that it will compress over bumps and then expand over holes. The problem with a loaded spring is that once compressed or decompressed it will recoil with just a bit less energy than was put into it. The cycle will continue at the spring resonance until eventually it comes to a stop. This effect would be detrimental to the performance of any vehicle and results in a rather uncontrollable ride. This is where the dampener comes into play.

Dampeners

To control the recoil and resonance of the spring, the dampener transforms the springs' mechanical energy into heat. The way this is accomplished is by forcing a perforated or valved plunger through oil in a tube. Changing the valving, the size of the plunger, providing additional oil volume in an external reservoir, mono- or twin-tube design and nitrogen charging the damper can all affect the performance characteristics. There is not one magic combination that works well on every car. Overall weight, intended use and corner weights are just some of the factors that will affect the way the appropriate dampener is designed. The easiest demonstration of this could be the comparison of a time-attack car and a baja truck. Both are competitive vehicles, but the Baja trucks may require suspension travel measured in feet while the travel on the time attack car would be measured in millimeters.

For more on this article and more grab a copy of DSport Magazine on newsstands and tuning shops nationwide!