Hey guys. First post. I've tried searching terms like "10.5" "max size" and others; currently I'm skimming page by page in the 'ultimate' fitment thread...

So.

I have a 2011 Infiniti G37S 6MT. Mostly out of convenience I switched from stock to an aftermarket set 10.5-275/30/20 + 9.0-245/35/20 that I found on facebook market in a combo tire/rim sale. These tires need to be replaced now and I'm considering going up to 285/30/20 and 255/35/20. So I'm only changing the width by 10mm. Here is what happened, I recently moved to an area that snows and gets near or below 32 for a few weeks each year. My front driver tire came off the bead of the wheel rim itself. I was close enough to return home in time but unfortunately I let the tire rot out of digust/anger; plus, my reasoning was that they were too stretched to begin with and going up a width size wouldn't be a bad idea.

Here's the thing though too. I have a set of Tein Flex Z coil overs I plan on installing at some point in the future. I know that changing the aspect ratio will add overall size, for example on the same size 20 rim a simple calculator reads a difference of 26.7 vs 26.5 inches. However, my own simple math indicates that I might gain 3 inches (30% of 275 = 82.5 vs 30% of 285= 85.5), though I'm positive something is wrong with how I'm calculating it or how the added 3 inches would be affected by the stretching of being mounted on such wide rims and if that will be enough to compensate. Right now on the 275's I can get three fingers in the rear fender gap.

I worry because of the possible gap issues I may face when dropping with the Flex Z and running 285+255 20's. And the reason I want to increase by the 10mm is so help reduce the bead disconnect issue I've just experienced.

I knooow something is being fit together wrong in my head, could anyone help me out? It's been a whiiiile that I've done much like this with cars. Thanks everyone.