The front never really rubbed, it was always the back when i would corner hard or hit a slight bump in the road.. it was just hitting the inner arch and i presume something above that.. So you reckon that they will be fine.. do you have any pics of your wheels.
I just put GTA alloys on my 156 V6, 17 x 225 x 45. I have about 10mm clearance on the front upright and about 10mm and i would be hitting the rear spring. I have really run out of space there. I honestly dont think you could go bigger. No expert though.