need help with SPEEDO CALCULATOR

**Boost** · October 16th, 2007

Hey guys,

Lately I have been having trouble with my speedo calculator. I have the latest version of everything, and when I click on the speedo caclulator and type in the tire size, it doesn't automatically jump to the adjust %. It used to do that before. Even if I click on the tab for the shift point correction the adjust % is 0. Has anyone encountered this or do I have to do it differently?
Please help, speedo adjust is big business on the Duramax since it can't be done by the Tech 2. Thanks a lot.

**Boost** · October 16th, 2007

And yes I do hit APPLY.

**Blacky** · October 16th, 2007

The shift point correction is a manual task now. You need to enter the original and new diff and tire sizes. The speedo calculator will then calculate the shift point adjustment percentage.

Obviously that process assumes that the shift points were correct with the original settings.

Regards
Paul

**Ninety8C5** · October 16th, 2007

I input old & new tire size and diff and the 'Adjust by:' stays at 0.00. Is there somthing else that needs to be selected/clicked on or should the 'Adjust by:' change as you input info?

I just tried several other years and it looks like it doesn't work on 1997/1998 tunes. On other years the original tire size and diff are filled in. On 97/98 cars no original data, but even putting in old & new data doesn't cause 'Adjust by:' to change.

**Boost** · October 16th, 2007

Thanks for the input Blacky. Will try that and give feedback.

**Blacky** · October 16th, 2007

Originally Posted by Ninety8C5

I input old & new tire size and diff and the 'Adjust by:' stays at 0.00. Is there somthing else that needs to be selected/clicked on or should the 'Adjust by:' change as you input info?

I just tried several other years and it looks like it doesn't work on 1997/1998 tunes. On other years the original tire size and diff are filled in. On 97/98 cars no original data, but even putting in old & new data doesn't cause 'Adjust by:' to change.

The adjust by should change each time you change the values in tire size and/or diff ratio.
While testing it I noticed that entering a new tire size in inches calculates the wrong tire size in mm. So fo accurate results (until we get the next release out) you will need to enter the new tire size in mm.

See before and after screen shots.

Regards
Paul

**Ninety8C5** · October 16th, 2007

I've attached a screen shot of the Shift Adjuster when I tried it on a 98 Vette. I've also tried a 98 Camaro with the same results. The 'Adjust by:' stays at 0.0 even if I change the diff. ratio.