[MarkyMark]

Illusive,
I just now read all the information you posted at the top of this thread. Thank you for doing the work. It is very well done, except your description of the tire size is wrong. In your example, you used the size 205/40R17. You stated that the 205 is the width of the tire in millimeters. This is correct. This first number is called the section width. You then stated that the 40 is the width of the side wall in millimeters. This is not correct. The "40" part of the tire size is called the aspect ratio. It indicates that the sidewall width is 40% of the tread width. To better understand my point, compare a 205/40R17 and a 275/40R17. Both aspect ratios are the same, but the height of the sidewalls are not the same. Hope this clears up any confusion. Once again, nice work.