Not Sure How To Title this Question: Tires wider than Rims?

[speedydragon]

I own an 01 b5 avant that came with the 11/how ever many spoke "sport package rims" and found out the previous owner, my mom, had put some 225/55/16 tires on a 16x7 rim. If my calculations are accruate, 225mm is around 8.6-8.8 inches. How does a 7in wide rim fit in such a large/wide tire without leaking air? I am currenty rocking 18x8 b7 a4 s-line/b7 s4/Rs6 look alike 18x8 rims. These came with 235/40/18. Again, if my calculations are accurate, 235mm is right around 9.1-9.2 inches. I have read that wider tires will protect your rim from curb rash and such, will running a 225 tires on my 18x8 protect my rims like running 235s?

Thanks in Advance!

P.S. Feel free to come up with a better title for this type of question/post

[VMRWheels]

225's can fit on a 7in wheel fine. It might look slightly bulgy but its fine.

-Charles@VMRWheels

[Doc@tirerack]

225/55R16 has a rim width range between 6" and 8". 235/40R18 is between 8" and 9.5" The difference in "extra" sidewall will be minimal for the purpose of wheel protection, unfortunately.

[speedydragon]

ahhh. But how does a 7in wide rim fit into an 8.6in wide tire? Even thought I had that on my car, but in my imaginative world, that can't seem to work :| thanks for the replies though :]