Rear steps to one side over bumps

[Mandinca]

I recently swapped stock suspension for BMW performance suspension, also added the Whiteline rear subframe "inserts" and put 18" rims on.
Had an alignment done and now when I go over bumps in the road the back steps out to one side slightly. Does this sound like bad alignment or something else ? No knocks or rattles, just a small side step. It usually does it when going over the patches of road where the top layer of asphalt is missing, kind of feels like it slips sideways down a small hole in the surface. Never had a car do this before.

Any ideas anyone ?

[tracer bullet]

Sounds like lowering created a little rear toe issue. I'd say alignment. Tires aren't quite pointed straight and are taking turns trying to be the tire that does it.

[Mandinca]

Thanks, I was thinking something similar but not trying to get ahead of myself. Visibly they look to be slightly toe-in but the spec sheet from the alignment does not concur....
There were some issues with getting the camber within spec so my guess is they wound the camber up all the way to get that within spec which then affected the toe.
So....what are my options ? The camber adjustment is with the eccentric bolt and is maxed out. I see adjustable arms of all descriptions available but don't know where to even start with this. Should I just get adjustable toe arms and put those in, get an alignment and see what happens ?

[1and1]

Start with the easy- what kind of faith do you have in the shop that did your alignment?

If even slightly on the "not 100% positive they kick ass" side of things you may want to contact your local SCCA chapter and ask who does good alignments in your area- the autocrossers will know who's doing good work.

[Mandinca]

First time I've been there. It was a bit of a rush situation so I had to find one that had a lift that was low enough - apparently a lot of the local places haven't heard of driving cars up on wood boards.....useless.
Thanks for the SCCA tip - I'll check them out.