Hi.
I would first head on down to a local wheel alignment shop as you will need one given fact that you have fitted alternative wheel/ tyre package; alignment will be out.
As per you suggested problem, suggestions are though will be clarified at point of wheel alignment;
-your car has been involved in a collision at some point
or
-mismatched, incorrectly replaced strut or lower control arm from a differing model
- severely bent strut
take some quality pictures of both sides with the wheels removed, and we'll see if we can help.
cheers