Mike Eaton explains how to find your coils spring rate using a simple equation.
This process is useful for those seeking to cut their coil springs, as it shows how cutting coils lead to a stiffer ride.
(Hint: ordering new coils with custom specs, and you can preserve or even enhance your ride quality and stance. A must for dedicated hot rodders and casual cruisers alike.)
When you cut coil springs you will make them stronger. The spring rate increases. How do we calculate that? It’s very simple.
Take 11,250,000 times four times the wire diameter, then divide it by eight times the active turns, times the mean diameter of the coil cubed. That gets you the spring rate.
UPDATE: To make things easier for you, we have built this handy dandy calculator:
Input your coil's measurements to find it's spring rate.
