I want to raise the rear of my iroc up a little and I was wondering how do you know if the rear springs are shot? My rear sits almost level maybe a little lower than the front, If i jack up the car (so the rear hangs) I could just about pull the springs out without undoing the shocks. If I bought some replacement springs it would raise it up??? Is there measurements I can take to tell err? I was going to put in air shocks but heard the ride is ruff and they could punch out the shock mount. But i'd like the rear to be up a little bit more than the front.