[Swifty1638]

Using this formula: Width x Aspect Ratio = Section Height
Section Height x 2 = Combined Section Height
Combined Section Height + Wheel Diameter = Tire Diameter
I came up with this for the 3 following sizes:

Stock: 205/55/16

205mm X .55 =112.75mm
112.75mm X 2 =225.50mm
225.50mm + 406.4mm (16"rim) = 631.9mm/25.4 = 24.878in.

235/45/17

235mm X .45 =105.75mm
105.75mm X 2 =211.5mm
211.5mm + 431.8mm(17"rim) = 643.3mm/25.4 = 25.327in.

235/40/17

235mm X .40 =94mm
94mm X 2 =188mm
188mm + 431.8mm(17"rim) = 619.8mm/25.4 = 24.402in.


Looks like the 40 profile tire is a bit more fitted to the stock size, but offers less sidewall "cushion" that the 45 does. 45 also allows for a slightly taller wheel/tire setup, meaning a LITTLE longer gearing.


-A. Swift