[Jackpine]

Originally Posted by onelildude

I'll try it and see what happens

If you are going faster than what the dashboard (and Gryphon) speedometers indicate, the number you have entered for Tire Size (TS) is too small. Also, since you are using the Custom Options menu to set the TS, you need to verify that your Gear Ratio (GR) is accurate too - it may well be incorrect.

Based on 35 inch tires, I get a TS value of 2709mm. That includes a 3% squish on the unloaded circumference of 2793mm. Try something in that range and remember to push [Enter] after you set both the TS and GR. Then, scroll to "Done" and press [Enter] to start the programming process. If you accidentally press [Menu] at any of these steps, you WILL NOT apply your settings.

And, JWBFX4 was correct when he said there will be a 2 mph difference between the dash speedo and the Gryphon speedo. If you can get the Gryphon speedo to agree with your GPS, (both indicating your actual speed), the dash speedo will indicate 2 mph faster at 70 mph (it has about a 3% error built in).

- Jack