Sounds like you have something binding in there. Those ladder bars should work very free. If you have access to a set of scales I would scale the car and make a preload adjustment with it on the scales and see if it makes a difference in the corner weight. If not then you definately have something bound up or broken as in the bracket pulling away from the rear end housing or something of that nature. It doesn't take but a flat of a turn to make a noticeable change with a free and properly operating suspension.
As far as just turning the bar thing...there's no way I can tell your experience level. You don't say so I can only start at the basics.
George