Did a speedo check today to see how much it’s of.

Looks like 5.7%

70 indicated = actual 74

80 indicated = actual 84.6

Did check with a GPS app on the phone and with a Lidar “gun”. (Lidar being the most accurate)

Not sure if I bother spending the $300.00 to get the hardware to reprogram the tire size, doesn’t seem worth it for that small of a discrepancy