[Oldporsche]

Wear in the upper bearing of the distributor allows the distributor cam swing in a larger radius. This reduces the amount of time your points are closed thus reducing your dwel time. You can compensate for this by closing up the point gap slightly.

I have been around this distributor thing a few times myself. As Roland says, Ferrari price level, cheap quality. I have seriously persued using a billet MSD distributor from an even-fire V6 motor as a replacement distributor for the 911. (Good quality, cheap price) This would be a drop in and could be recurved for any camshaft.

As Roland says, use any Bosch distributor that has the appropriate advance/retard mechanisms. Rebuild it to take the play out of it. Get the advance curve specs for your motor/camshaft from the spec book or shop manuals and take the distributor to your local hot rod shop that recurves distributors. They can verify the curve or match your curve to the appropriate curve for your motor/camshaft.

Good luck,
David Duffield