I have a 32mm Front Swap Bar on my IROC with urithan(Spelling)bushings...I think it might be a solid bar because they guy before me said that it was aftermarket and don't IROCs come stock with 34 or 36 of somthing........I have heard that you can have too much sway bar.....anyway the car is lowered 2" with red springs (Jamex?) and handels with like NO body roll....what size bar and what shocks would best suit the lowered IROC.

 

A lot of IROC-Zs came stock with a 32 mm front and a 24 mm rear bar.

You are right, You can have too much swaybar. With stiffer springs and a swaybar set that is too stiff the car won't roll enough to plant the outside tires into the ground. This is most noticable on wet pavement, but it has an affect on dry pavement handling as well. To optimize handling, you need to find a balance between enough body roll to plant the outside tires, but not so much body roll that you lose responsivness or that it affects your front end alignment too much (ie. more body roll = more camber loss = less outside front tire tread on the road in a turn.)

Each individual car will need to be tuned seperately due to so many variables, but I would be willing to bet that a 32mm isn't too stiff. It isn't really that big, relatively speaking.