Biggest tire in Stock rear fenderwells

Hey Guys I really am not in the mood to tub the Scamp so I was wondering whats the biggest tire you have fit into a stock wheel well (ignore leaf spring clearance) and not had issues with rubbing? I will have the correct offset wheels but I want to know. I had a minitubbed dart that I squeezed 28x11x15's in but that car was not much of a street car and the tubs only went to the frame rail.