Rotor/Reluctor Phasing Question

The vac can on the distributor is adjustable. We have already put 3 turns CCW into it, but with 20 inches of vacuum at idle, it still adds about 28 degrees. How many turns CCW can we go before the adjustment runs out ?

...............r u sure ccw is the right way.........i have not did this in alota years and not very often..........kim.......