Help me tune my dizzy?

seabee said

Out of the box my "ready to run" distributor had 20' mechanical all in by 1750rpm. Bending the spring tabs got me to about 2500 now.

The problem is that vac advance is another 20 so having an intial around 22' will get you above 60'. For my engine, that was getting lower engine noise, so I have the vac disconnected.

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This is the exact wrong thing to do.
Firstly the power timing is now 20 plus 22=42, all in by 2500. This is perfect for part throttle cruise, but will hammer your bearings to death under full power at 2200rpm and probably still be hammering well into the 4000s, and beyond. If you disconnected your secondaries the engine might stand a chance. Furthermore with the vacuum advance now disconnected, there will be large periods of time that the engine will not be receiving the advance it needs and so it will waste fuel being as it is retarded for the mode of operation.
A much better idea is to back up the idle-timing to 14 degrees, and let the power-timing be 14 plus 20=34@2500 .This will at least be correct at WOT. Then hook the vcan back up. The 20 degrees in it will not be applied until the manifold vacuum at the sparkport tells it to. So it might add 4 degrees by say 1400 rpm and 4 more by 1700, and 4 more by 2000, and so on until it is all in by 2600 under light cruise. Now the engine might be seeing ; 14 plus 20 plus 20vacuum= 54* @ 2600rpm at hiway cruising. This may be just right. And when you are cruising along at 2600, and you decide to floor it, then the 20* in the Vcan will drop out leaving you perhaps in second gear @ 4000 or so rpm where the all-in timing is just 34*. Now yer talking!
This covers all the bases.
It may not be 100% correct, but at least the engine won't hammer out the rod bearings or split off the skirts.