[atruelunatic]

I know that speedometer is generally off by about 4%, but after changing to AD08's (285/30/18) from the stock PS2 (265/45/18), the difference increased by a whole lot. Cruising on the highway, the difference is roughly 7mph. I was fine before when I had a 2 mph difference, but 7 is sort of too much. I'm always caught off guard now when I notice my speedo at 87-90MPH and then remember I'm going 80-82 MPH. Any way to fix this? And does this effect my odometer reading by much?