Compression VS. Octane

Duggie said

It sounds like a Dynamic compression ratio of 9.0-1 would keep me in the ballpark for pump gas with my shinney new BBD 2 barrel. I could go on a play with the distributor advance curve as free time or 'ping' urgency dictates?

With the needed measurements confirmed on my slant, I could then ask the machine shop to mill the head to a target cc for the desired Dcr.

Yes?

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A static compression of 9:1 may run regular gas in a light vehicle, but you will be leaving ignition advance on the table.
I would shoot for a static compression of 8.5 to 1, that would allow you to run an aggressive ignition curve and have a safety factor for hot weather, big hills, bad gas.
I pay attention to dynamic compression ratios, but I build engines around static compression ratios.