[JJ 911SC]

Hi Bill

My second time typing this so hopefully...

I'm going the other way, 7.5" --> 7"

Before I found this one, I was on the Tire Rack site and understand the rule of thumb about a change of .2" in section width for every .5" in rim width change. They also mentioned because tires have flexible sidewalls, a single tire size will fit on a variety of rim widths. A tire's rim width range identifies the narrowest to the widest rim widths that the tire is designed to fit. The width of the rim will influence the width of the tire. A tire mounted on a narrow rim would be "narrower" than if the same size tire was mounted on a wide rim. NOTE: Because the overall diameter of a steel belted radial is determined by the steel belts, there is little, if any, change to the overall diameter of the tire due to differences in rim width.

So logically if the tire is squeeze in by .2", the displacement got to go somewhere but not in the overall diameter dimension due to the steel belts. Probably due to this small variation, the program in the link below does not record any significant changes.

So when everything is said an calculated, is this change OK without changing the tire. If not, which way in width/ratio should I go as the present set up is at the limit before rubbing (on full turn at low speed)?

Cheers

JJ