I really think that what you need is a pair of good springs. As your car is sitting too low in one side, something must be wrong and this will affect handling in several ways:
- The spring constant must be wrong which may cause vibrations because the damper and spring are no longer matched.
- The camber of the rear wheels is different either side. The semi-trailing arm suspension employed in the Murena is designed to give -2 degrees camber in neutral position, but this changes with suspension travel to give an optimal grip during cornering. If the camber is wrong, this affects the handling of the car in several ways.
Have you checked your tyre pressures? 2.5 bar rear, 1.8 bar front.
I am certain that you will be happy with a new pair of standard springs than with any thing else, Krede