unstable at high speeds.
 

so Ive been having this problem with my car...at speeds higher than like 55mph, the car feels unstable, like if I take a curve a tthat speed, feels like Im gonna lose control, feels like the rear end is gonna break loose a little just by switching lanes...anyways, my question is what can be causign this? could I have broken an integral part of the suspension system? it started when I took my car to the track, when I was doign 1/4 mile runs, I did a couple, it was fine, then I started noticing that at the end of the track the car was getting unstable..could I have broken something at the track? maybe a sway bar or something?

Have you gotten an alignment and had your tires balanced?

check make sure your rear swap bar is there, and connected right. you somehow may have broken a weld or something. is your car lowered? if so, on what?

its lowered on hp coilovers

did you ever get an alignment after you lowered it?

considering the age of the car i would check the rear upper control arm bushings. mine does the same thing, and i saw how bad my bushings are.