If your car bounces it needs new or upgraded shocks/struts. I have poly bushing up front and FTBR stuff out back. While on the stiff side it doesn't bounce. My main rubbing issues are the back tires on really hard dips. And that's usually only if I have a passenger and a full tank of gas. Though when I was really low I was told I shot sparks from the pipes under the diff. The clamp bolts were a little wore down too. I've since raised the car a little.