I never did get anything resolved with tire size in Forscan. With an SCT tuner, they have an option to adjust gears/tires. Could try that method. With Livernois, the only way to change the Speedo is to get them to make an adjustment in their tune. I've asked multiple times and requested a tune update from Livernois for the the tire size. Chrs Rekuck told me that pretty much it's as good as it's going to get. Since March and that rubs me wrong. They made one adjustment and went too far, now they won't adjust more? They went too far. Go back to original set point and adjust 50% of what the adjustment was.