Intrax Springs

Just bought this car 2 days ago, and already found a problem. On a decent dip this car will bottom out. And, not in the fenderwell, the crossmember sounds like it scrapes the ground on a good dip. Anyone else have this issue with these springs? If you have any ideas where to pick up some H&R springs for a good deal online, and an approximate cost to have them installed would be much appreciated? And whats a good spring rate to prevent this from happening?

DO NOT BUY INTRAX SPRINGS