Actually, aspect ratio determines the height of the sidewall, which contributes to the overall diameter of the wheel and tire package.mblommel said:There is also another possibilty. If I recall correctly the aspect ratio of the tire also has a bearing on it's actual overall width. I believe it is possible that a 205 45-series tire is the same functional width as a 225 55-series tire.
Check out this page for more info:
Hope this helps, and it still could be a misprint.
You can also check out the FAQs on wheels and tires now in the EXTERIOR STYLING forummblommel said:Thanks for the tech info, I need to re-read the page I hyperlinked to, my reading comprehension must be slipping!