03-02-2012, 08:29 AM
Once a car is on the ground (i.e not jacked up) the helper springs are fully compressed and do nothing other than act as a spring set for the main spring. Theyre only there so that when a car is jacked up the helper spring 'expands' and keeps the main spring seated, otherwise the main spring would just flop about and may not seat properly again once the car is put back on the ground.