MY dad has my new springs i just got at his work, where he is sand blasting them (they are used slightly) AND he has several pieces of equipment at work for compressing springs and measuring tensel and a bunch of other stuff. HOW do you exactly measure spring rate? Do you just see how many lb/ft it takes to compress the spring alll the way??

 

It's measured in lbs to compress it one inch.
Usually its done at what the installed height (preload) is as the starting point. So from there (0point), you compress it 1" (using a dial indicator to measure). The lbs it took to go that one inch is your rate.

Be careful as you can see this is a potentially veddy veddy dangerous operation.

 

thanks man, BUT wut is the preload for our cars?

 

Measure the spring length when its installed. Every mfg's spring will be different as they are different free lengths.

If the springs are linear rate you should be able to go one inch to preload it and then go another to see the rate. But using installed height is more accurate.

 

Woah, cool to know Carl, thanks .

~T.J.