Unhook the front sway bar, leave the rear. Get the front end to move as free
As possible and that might include different torsion bars and almost certainly shocks. Then get a good double adjustable rear shock, and start tuning. Take way too many notes, on every pass. Make one change at a time and compare.
Sorry for the red X. I very rarely use the X but what you said is all wrong. Superstock springs are designed to move because they unload and plant the rear end onto the track. Restricting rear axle movement is opposite of how they work.
