As far as performance goes, BMW changed the diff from 3.91 to 4.1 for the 3.0 which is 4.1/3.91=1.049 to help out off the line. You'll definitely feel three difference but again comfort vs. performance.

At 2.8% bigger tires, that makes 200 ft·lb become 200/1.028=194.553

With 5.2% bigger tires:
200/1.052=190.114.

6 or 10 ft·lb loss. It's something a racer would be concerned about, I doubt you would.

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2011 E70 • N55 (me)
2012 E70 • N63 (wife)