So I was doing some research and people were saying than the front and rear spring rates should be different? It seems to have something to do with motion ratio and under/oversteer, but how exactly are they affecting the spring rate? Thanks in advance.
The primary reason is the weight distribution of the vehicle. Vehicles tend to have a big heavy engine up front and not much weight in the rear. The ratio should be closer on vehicles with close to 50/50 front/rear ratio. Vehicles with engines in the rear should have higher spring rates in the rear.
To increase over steer - softer up front, stiffer out back
To increase under steer - stiffer up front, softer out back