Hi friend, I also have 17'rims and it's rim width is 7' wide (17X7). I currently have a set of 225/50/17 on them and use to have 215/50/17. Both these tire sizes (225 & 215) will work although I find the 215's much more responsive and lasting longer. The reason is because the rim's 7'width is ideal for supporting the sidewalls of 215 tires and not 225.
My reccommendation is to try buying 215's instead of the 225's for your rims. You'll regret installing 225's on them. I know that 215's are rare and hard to find, but put the effort to find them. http://www.tirerack.com should be an insightful site to do your research.
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