A properly tuned spring system provides the muscle needed to transform the power derived from the engine of a racing car to the track through optimum adhesion. Suspension tuning is a precise balance. On one hand, the spring system should be soft enough to compensate for road irregularities assuring permanent road contact, while on the on the other hand the spring system must be firm enough to reduce the body roll, squat, and dive of the vehicle during cornering, acceleration and braking. For optimum balance, Eibach has developed our world famous ERS double spring system. By combining more than 700 different single spring components, the suspension engineer or weekend enthusiast can create nearly unlimited combinations. Our ERS double-spring system is unsurpassed in performance and flexibility. The ERS systems relies on a Main and Tender spring concept that provides a softer initial rate when both springs are compressed together, then delivers the desired firmer ending rate once the tender spring closes completely. The Main spring has a linear-rate characteristic and determines the final rate of the system. The Tender springs are available in a variety of linear-rate as well as progressive-rate characteristics and determine the initial rate of the system. A Helper spring is used to prevent the Main spring from becoming loose in the spring seat when the wheel is at full droop. The Helper spring, unlike the Tender spring, has very little spring rate, and therefore has no effect on the suspension characteristics of the vehicle. Up to 50mm of spring-to-perch gap can be covered with the use of a Helper spring. Connecting Plates are used to connect Main and Tender springs. Eibach offers both inside and outside diameter connection plates depending upon the dimension and function of the specific damper utilized. * Uncountable individual combination possibilities to create from standard spring components ex stock * High spring travel (deflection) and therefore high end loads at short mounting lengths * Block resistance * Surface treated through shot-peening * High dynamic durability (component longevity) * Precise tolerances * High quality corrosion protection by phosphating and epoxy coating * Individual protective packaging * Easy identification (imprinted with Part no.-indicates spring rate and physical dimensions)