The encoder settings and steps need to be correct, but if you have all that, the pitch should be based on the thread pitch of the lead screw and your belt pully ratio. The lead screw is 8. The belt flips it to a negative. It would be positive if it were a direct drive. If you have a 3:1 gear down (bigger 60 tooth gear on the motor). If you have a 1:2 gear ratio (wider belt and bigger gear on the router, not the motor) it will be something else. What does your belt setup look like?
this is a 3:1
This is a 1:2
