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Coil Suspension After

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5. After: Here you can see the new-variable rate Old Man Emu coil spring installed. Note that the top three windings of this coil are much closer together than those of the factory spring it replaced. This is what gives the spring a "variable" rate. This type of coil spring provides two distinctive benefits over traditional constant-rate coils: First, the regular-looking coil wraps ensure a smoother ride over smaller bumps because they are set at a softer rate than factory springs. Next, the tighter windings prevent harsh energy spikes, also known as "bottoming-out events," because the additional spring-wire material increases the spring rate at the top or end of the spring's range of motion. This type of spring is much more difficult to manufacture than a regular constant-rate coil spring.