Originally Posted by
Bald Paul
It's far too early in the morning for those calculations (I haven't even finished my coffee.)
But, imagine on the left is the cross section of a tall tire on a small wheel, and the right is a low profile tire on a larger wheel. Here's a hint: the rectangles (tires) are all the same.
True, but this requires the tire width to increase a lot more than is typically the case. In the Camry tire sizes listed above, the widths vary from 205 - 235 mm while the sidewall heights vary from 94 mm to 133.25 mm (assuming I'm remembering how to read tires right, literally one of the worst measurement standards ever conceived). So widths vary by 30mm while heights vary by 39.25mm, meaning that the volumes don't remain consistent even though the recommended tire pressures are the same.
For the record, big SUVs suck whether or not low profile tires and their relative pressures have anything to do with anything.