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The Suspension Rates page determines wheel rates and suspension frequencies based on the spring rates, the motion ratios, and the sprung and unsprung weight at each wheel. Accurate measurements are essential for meaningful answers.
The motion ratio is defined as the distance the spring moves divided by the corresponding distance that the wheel travels. This is most easily calculated by measuring from the control arm inner pivot point to the spring mounting point on the control arm, then measuring from the inner pivot point to the outer ball joint.
Sprung weight is defined as everything supported by the springs.
Unsprung weight is everything else on the vehicle.
Some parts, namely pieces of the suspension, are partly sprung weight, and you will have to estimate the proportion. Often, 50-75% of items like springs and control arms are considered to be sprung weight.
If you know your wheel rates but not the spring rates or motion ratios, enter the wheel rate for the spring rate, and enter 1 for the motion ratio.