Geometry calculations:
change in ride height: -8.3 mm
tire height: - 16.5 mm
rolling diameter: -51.8 mm
change in drive ratio: -2.4%
actual speed when showing 55 mph: 53.7 mph

If you went with a 255/45 you only gain 9 mm in height with a change in drive ratio of 1.3%. You also get a little more pothole protection if you get my drift.

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#1352 Mysterious black. Ordered 4/15. Delivered 11/25. First ticket 11/27