I have 17" x 10" wheels with ~ 34 mm offset and 275/40 tires on my Vibe. With a 1 -1/2" drop, I get a little scuffing of the rears against the outside fender lips on big dips, but 235s would be 20 mm (0.79") narrower per side, so you should be fine.
Lowered or stock, the worst case is when you hit the bump stops on a big dip with a full load. However, my sidewalls barely catch the fender lip. Even 1/4" more clearance would eliminate the contact. I plan to grind a bit off the lips, but haven't got to it yet.