Another timing curve question

Thanks. I hope he'll jump in too ;)

The problem with an advance that starts below idle speed is that the idle will never be really stable... less RPM, less timing, less RPM, stall... so I have to have some way of setting it up to start advancing at no less than 1200.

On Moparts there's a reply already with similar combo, and he just uses the one light spring to crank, then all in once it's running. Says that worked ok on the street for him...

I'll sort out the vacuum advance (runs around 14-15" at cruise) last.