tire size chart

Nice chart. Not to be critical, the numbers are a good starting point. The other factors that will affect tire height are:

1) Width of the rim. This one will affect 60 series tires and higher more than 55 series and lower. Example, if you mount two tires, size 215/70/15, one on a 15x6 rim and one on a 15x8 rim. The 15x8 will have a shorter profile because you are stretching the tire out over the wider rim. BFG use to have the widths and heights for each tire sizes listed in their catalog when mounted on a specific rim width.

2) All brands are not the same. The sizes between them will be relatively close, for example, if you line up a Firestone, a Goodyear, a BFG, and a storebrand (Sears/Costco/PEP Boys) size 215/70/15. The storebrand will most likely be the wimpest looking. (more narrow and least amount of starting thread.) YES, all tires are not created equal. A 215/70/15 in a cheaper brand may start out around 8/32 of useable thread and most branded names start off at 10/32 useable thread. (60 series and above. 55 series tires and below usually have lower starting thread due to being performance tires. ) Might not sound much, but if you think about it, that's like 20 percent extra rubber life! As for the branded names, they all have their own special patent formulas to make the tire a little taller or wider than their competitors.