Well, the theory turned out to be 100% correct! It took about two hours to do the complete installation and timing synchronization and the engine has never been happier. There is a guy on the Holley forum with an excel spreadsheet that you enter initial timing, mechanical advance and vacuum advance along with RPM and vacuum values for both respectively and it calculates a timing table to feed to the ECU. After all is said and done, the engine is now pulling 21" of vacuum at idle and has a much better temperament while cruising down the road. Still working a little bit on the WOT tuning but it's close.
We ended up using the following for parameters:
Crank Timing: 12°
Base timing: 15°
Mechanical Advance: 22°
Start: 1000 RPM
All-In: 4000 RPM
Vacuum Advance: 8°
Start: 5"
All-In: 10"
I may end up adding a couple more degrees of mechanical and/or vacuum but we're going to give it a little run-time and see how she responds.
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