What should I check (Camber settings)?

[M0T]

I took my car for a 4 wheel alignment today and was told the camber on all of my wheels was out.

3 Wheels are all out by the same amount (negative 1 degree 50 minutes) which is a result of the lowering, but one of my rear wheels is out by negative 2 degrees 20 minutes. Since the camber is non adjustable what would cause this huge difference?

Wikipedia lists the rear suspension as:

independent multi-link rear suspension, which is made of telescopic vertical strut with coaxial spring and two transverse links with different lengths and a longitudinal strut, with this structure the rear wheels have a small passive steering ability.

 

[Dogbreath]

3 Wheels are all out by the same amount (negative 1 degree 50 minutes) which is a result of the lowering, but one of my rear wheels is out by negative 2 degrees 20 minutes. Since the camber is non adjustable what would cause this huge difference?

Assuming it's been measured correctly...

30 minutes (i.e. 0.5 degrees) isn't really a "huge" difference on a production car. A Google shows that the factory tolerance on the 156 is +/- 20 minutes for starters, so it's possible the car was actualy in spec before it was lowered.

It's also possible that a previous owner has clobbered something with the wheel on that corner, slightly bending something, or a bush/balljoint has worn.