Assuming that is the static timing, it should be advanced from that for 9:1. Advance the distributor with it idling for the best running and give that a go.
Also make sure that both centrifugal and vacuum advance are working.
Apsrt from these, especially if it seems to be running too rich, I would suspect the carburettor, possibly something dried out while not used, or if you overhauled it, incorrect assembly (but I'm not familiar with the Stromberg).
Bookmarks