As a backup plan, I want to make sure that this setup will fit my 2013 Prius without adding spacers or doing any mods. Does anyone know if a 17.5 wheel will work with 215/45/17 tires or should I go with 225/45/17? What is the difference in the look of 215 vs 225? The offset is 45.
Have you been using a tire size calculator like this to select your tire size choices? Both of your tire choices would be acceptable with the 225 width tire being a dead-on match for tire diameter compared to the stock 15 inch tire. You should then base your tire decision on whether a LRR tire can be found in that size, keeping in mind that the wider profile tire will be heavier and have more mpg loss due to friction than the narrower tire if all other things are equal.