Early single ohv camshaft types.

Hi

Is there a definitive camshaft comparison for the pre war singles?

For example cam markings to follower types and the years/models.

I have cams marked 20P in and ex and they go with radiussed followers I believe. 1930/31 18

Then there are ones marked I5 and EE which I think go with flat followers. SV 16h? 

It would be beneficial if we had a listing somewhere as the numbers on the cams do not tie up with part numbers in the lists.

Paul