THE LIE BEHIND DUAL RATE COIL SPRING
The term “Dual Rate Coil Spring” has been echoing around for some time and we can’t lay silent anymore; put down your “Editor Irons” voodoo dolls and hear us out… A dual rate coil is only a dual rate coil if you can stop one of the “rates” in the coil from moving during some point in the suspensions cycle. In a full-on racing style, multi coil, coilover shock, this is done on a regular basis with a “spring stop”. These isolate one spring and put a portion of the wheels travel on the other instead of using the two springs together. This transition of two springs motion or single spring motion defines the “dual rate”. This is not done with the single coil springs on the market dubbed as “dual rate”. If you compress a single rate coil spring to the point that its spring rate becomes non-linear, or the coils touch each other to stop moving, we’re sorry to inform you the life expectancy of your springs has been shortened, drastically. On coil sprung vehicles like our JKU with a single coil at each corner, a “dual rate” coil is not possible without “stopping” one of the spring sections from moving.