Used the tool mentioned by Maxichon https://www.crossfireforum.org/forum/...ment-tool.html

255x35x19 deliver 10" tread width x 26" overal tire height x 3.5" wall height

275x35x19 deliver 10.8" tread width x 26.6" overall tire height x 3.8" wall height

285x30x19 deliver 11.2" tread width x 25.8" overall tire height x 3.4" wall height

I researched this heavily before buying replacement tires around 3 years ago. I was assured that the stock rear width would handle the 285's, but not to go larger.

Over two years later multiple track days, slalom events and the 4500 mile cross country trip from the west coast to CAA in St Louis last summer and no issues with bead "pop". I would classify that as aggressive driving.

Just because a tire has specific ratings, does not mean they all fit or stand the same. Each brand (and model within the brand) "lays" on the road differently. My first set of 285x30x19s were Nitto Invos. they looked like street slicks and had a very soft compound (wore out extremely fast). The sidewall did stretch over the rim a fraction (it actually helped prevent some rim rash). My Hankook Evo 112s are more flush with the rim and curv in at the top not quite as vertical as the Nittos.

However, when running the recommended 36 pound of pressure in the Invos, the tires had way too much sidewall flex as a result I generally ran 40 lbs all around. Funny thing is that if overinflated, the center should have worn first, they did not, it was the edges. Also, I don't know if it was the softer compound but the outside edge of the front tires showed excessive feathering.

The Hankooks have twice the milage (and more to go) and are running with 36 lbs with smooth wear across the tires.

Back to the original point. the 285x30 has a wall size of 3.4" vs the stock 255x35 at 3.5" I dont think I can even notice .1". However going to the 275X35 with a wall height of 3.8" a difference of .3" would certainly be noticeable AND measurable.

These are just my observations, everyone has to make their own decisions.