Originally posted by pnthr30
I may be wrong (I am a noob), but I thought that the way to calculate the height of the tire is to take the tire width x the aspect ratio. So the stock height is 195 * 55% = 107.25mm, the 205/55 would be 205 * 55% = 112.75mm, and the 205/50 would be 205 * 50% = 102.5mm
So the difference in height from stock to the 205/55 is 5.5mm higher, and stock to the 205/50 would be 4.75mm lower. So technically the 205/50 would be closer to the stock height, also with a lower aspect ratio the tire will handle better, do to the reduced height in the sidewall (more rigidity).
Is this correct?
Absolutely correct. However, this is for tire section height, not tire height. So if you have different rim diameters, you have to include this in your calcs. Total tire height would be section height + rim diameter + section height. A 205/50R17 would be two inches taller than a 205/50R15.
Ferd