Has anyone researched changing wheels and putting wider rubber on the rear?
I would keep the same 225/55R18 on the front but use a 275/45R18 on the back, which would need an 18x9 wheel instead of the 18x8 for the 225/55R18. I'm not sure the offset I would need.

I'm actually looking for a 17" solution for winter tires ... anyone do that? Any details appreciated!

Thanks!

I'm considering using the same 17" wheels that I had on my G35 Coupe for winter use. They fit OK, but are 17X8, which means that the tire sizes available are not optimal (2% speedo error). But I think I can live with that.

What have you turned up?

I haven't started looking in earnest just yet, but do have a couple of aspects to contribute:

1. The TPMS will be an issue as well. If TPMS sensors are not installed in the winter tires (which must be registered to the car, probably via OBD-II), the warning light will blink all winter long.

2. If you use higher profile 17" tires (as I plan to), with a similar "revolutions per mile" rating to the OEM ones, you can mitigate (or even eliminate) any computer-calculated speed/mileage errors.