There was a discussion on this spec wheels a couple of times before, and someone did mention they are "same concave" as wider ones, but it was not certain. I guess either the OP can confirm, or the vendor you are getting them from, afterall, they should know what they are selling
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Just because this 235 tire looks stretched on them, doesn't mean those could not be 8.5. My co-worker had 245 width Contis and they looked slightly stretched on 9 wide, no "fat" by any means... This is not too far off.