Start by measuring the angle of your springs from vertical in degrees (A), and then use the handy chart or accompanying formula below to determine your Angle Correction Factor (ACF).

Shock Angle              Angle Correction Factor (ACF)  

10°………………………………….. .98
15°………………………………….. .96
20°…………………………………. .94
25°…………………………………. .91
30°…………………………………. .87
35°…………………………………. .82
40°…………………………………. .77
45°…………………………………. .71

Formula: ACF = COS∠A°

Next, determine the spring rate needed if the spring is installed straight up. Then, to compensate for installations at different angles, find your Angle Correction Factor (ACF) using the chart or formula above and divide your straight-mounted spring rate by your ACF.

Example:
Straight-Mounted Spring = 200 pounds
Spring Mounted at 30° = 200/.87 = 230 pounds

Which means 230 pounds represents the spring rate needed when mounted at a 30° angle to equal the spring rate of 200 pounds when mounted straight up.