One of the chief benefits of air suspension is the springing material itself. With mechanical springs-whether coils, leaves, or torsion bars-the springing is based on the elasticity of the metal. With an air spring, on the other hand, the springing material is the air itself. Since it's a compressible gas, the amount of air in a spring determines its spring rate. "By nature, air is a very progressive spring," explains Bret. "The further you squash it, the stiffer it gets. Moreover, the frequency at which an air spring gyrates, or bounces back, is far less than that of a mechanical spring, which results in improved ride quality." Perhaps the biggest perk of an air suspension is the ability to change the spring rate by lowering or raising air pressure at the touch of a button. "With an air suspension, it's very simple to tune your chassis to prevailing track conditions. A car with coilovers can be tuned to handle just as well, but it requires much more skill and patience from the driver. An air suspension is much easier to adjust, which makes it more attractive," says Bret.