Actually,OT2 does not use ibo ratings and uses cam performance for spine matching.You can do as Dave is telling you but the spine will not change from 1 to the other,this is why I contacted them in the first place.Needles to say,I was very disapointed in the program and have gone back to Archers Advantage which does allow you to use actual speeds of your bow to get perfectly matched spined arrows.

I discussed this with them and this is what I was told because I was getting conflicting numbers.I have found it to beaccurate IF you have some way to calibrate the cam system.