Erratic cut sizes

I installed new upgraded stepper motors and belts. The install is complete. The machine worked as it should before the upgrade. I ran a square (cut at .1 deep) in the waste board to confirm that the assembly was square. I made this square 17”x17”. I cut the outline of the square from center. The machine did as I asked, but cut the square 21”x21”. I did this again for 12”x12” and it once again cut very evenly and straight, but larger than designed.

I have absolutely no idea why this is happening. HELP!!!

What are your $100, $101 and $102 GRBL parameter?
What distance to each axis travel when you command a 20" jog for X & Y axis and 2" for Z ?

There are several good videos on steps per mm, you can check out pawpaws workshop as well he has one. A couple links I had book marked are below. Steve

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