From 3.8Wiki
Wheel rate is just the spring rate measured at the wheel. To see the differences in wheel rates when using conventional springs vs. coil over springs I will show you a simple formula.
Conventional Springs:
Front - (spring rate)(.25) = wheel rate
rear - (spring rate)(.5) = wheel rate
Coilover springs:
Front - (spring rate)(.9) = wheel rate
Rear - (spring rate)(1.1) = wheel rate
To see what a coilover spring equals in a conventional spring
(C/O spring rate)(.9)(4) = Conventional spring rate
-Added by Greensteeda