It will bounce some, just gotta approximate, and if you are selling it, then they can deal with it as long as it runs to show them it does. I wouldn't worry much about total time for what you are doing. Was the timing chain also replaced with the cam? (hopefully) If not, that is the source of the bouncing, or the balancer can be bad, and has moved, and the timing won't set right. How does it sound at that setting? If it sounds ok, and the throttle responds good, call it done. If not, try to find a place where it does sound good, the throttle responds good, and it restarts good, and then quit.