Any site where I can look up factory spring rates??? kinda not PT

[PT Sportwagon]

I am looking to find out some spring rates. I have a 98 Grand Cherokee and want to do a budget lift. using a set of front springs in the rear, and spacers for the front. I was JY hopping and couldn't find a set of 6 cyd Grand cherokee springs, they only had V8s. I did pull a set out of a jeep comanche. I want to know the spring rates of the 6 cyd grand Cherokee and for the Jeep Comanche. To judge the amount of lift I am looking at.
Thanks

Tim

[Henesian]

Look up the springs on Rockauto.com, because they give you specs for some brands. Then use Herb Adams coil spring equation to find out the rate.