the wheels are 19 X 8.5 all around. The wheel is ACS Type III.
Thanks for clarifying.
Well in that case...let's do this with some math...
info: 19x8.5 with a 255/3019 ACS Type III (et 43 I believe) any spacer???
conversion info: 1" = 2.54 cm = 25.4 mm
wheel width in mm = 8.5x25.4
wheel width in mm = 215.9 mm
center of rim = 215.9 mm /2
center of rim = 107.95 mm
distance from mounting surface to the outside edge of the rim (RIM ONLY)
= 215.9 mm - [107.95 mm + 43 mm]
= 64.95 mm
Now the assuming the tire is exactly centered in the rim...
How much will the tire stick out past the rim edge?
= 255 mm - 215.9 mm
= 39.1 mm / 2
= 19.55 mm
So how far are you past the mounting surface...
= 64.95 mm + 19.55 mm
= 84.5 mm
So...your tire will be 84.5 mm past the mounting surface at the furthest point.
On a sedan I believe I did this same calculation with Dev's setup for my own purposes. He had a 323i sedan and was 82.5 mm past the mounting surface. He rubbed occasionally, but I never found out if he rolled his rear fenders. I forget what tire size he had.
For you...I say would be alright on a coupe with 255/35/19 if you roll the rear fenders. But if you want to really safe...get the Pirelli 255/30/19. The 255/35/19 is +26.8 mm compared to stock...while the 255/30/19 is only +1.3 mm
You will be fine with 255/30/19's on an 19x8.5 ACS Type 3 et 43 on a ci. That's my conclusion. Without rolling the fenders too.