Timing Curve

2500 stall PTC converter.
Haven’t detected detonation yet but haven’t been on the open road either.
I do have vacuum advance with 15* in it.
So I got advice to bring it in a little earlier (which I did) and to get it all by 2500.
So Mattax your concern is that the curve is too “fat” 1800-2500, needing to maybe be flatter there. I might be able to that with more of a difference in spring sizes. More two-stage ???