4l80 swap guys how the heck do you get the speedo to read correctly??

[MY99TAWS6]

My speedo is like 40mph off! Pretty sure this is causing my shifting to be very off also. Like it seems to go to 4th at like 20mph.This lugs the engine big time and car is undriveable. I had speedo set perfect for my tires and 3.54 gears. Why don't it work with the 4l80 swap now? Do I simply have to put in some value in the speedo section on hptuners to correct this. I thought the 4l80 segment swap fixed this.

[MY99TAWS6]

Ok think found the problem but don't feel like trying it out tonite in car its like 20F out there right now.

My original blended file had correct 40 trans/rev number for the 4l80 . But my speedo wasn't working right in the t56 so somehow put in 17 the t56 number. Then problem was speedo was way way out.

Now tried to simply enter 40 in the field but for some reason my file wouldn't accept it. The file is converted to version 2.22. I calculated proper numbers from my original file and entered them manually in my current tune file. So think that should work find out tommorrow if speedo is right. Have gps to check it.