an example of today's loudspeaker R&D

Hi guys, izzit ok to install the stock spring at rear and lowered sport spring at the front for a car?

I am getting fed up when carrying some passengers at the back, the car keep hitting ramps, especially sunway area.

Will there be any adverse effect? (too much difference of spring rates at the front and rear)

Or should I just add rubber spacer at the back to make it higher?