Speedo Recalc for New Tire Size
Just bought new tires and wheels for my 06 GTO and wanted to adjust my speedo settings to be more accurate because of the change. However, when I first went in to the Speeo Calculator I started off by entering my OEM tires into the calculator and the results were not even close to the OEM values in the tables. For example, for my stock 245/45/17 wheels (corrected tire size 3/1/07 @ 10:07 pm MST -- was 245/25/17):
Param: -> OEM Val -> Calc Value
H0101 -> 11792 -> 67536
H0104 -> 312 -> 1688.39 (the calculator inserts 636 here when apply is pressed)
H0136 -> 503 -> 487.98 (nothing happens here when apply is pressed)
H0139 -> 2540 -> 2049.26 (nothing happens here when apply is pressed)
Before I go entering the data for my new tires/wheels and really mess things up. I'd like to understand what's going on.
Any thoughts?