Putting on our science caps...
Does anyone have science/engineering data that might advise an ignition recurve with modern 15% ethanol/gas in mind?

We know it is harder to ignite, and burns more quickly, so if a hypothetical 8.0:1 360/390 had a perfect no-ethanol curve, what would the change (delta) be when switched to 15%?

Looking for the documentation more than personal experience.
Comments on tuning practice not needed.
Curves and references would be appreciated.


Total advance curves (with vacuum advance disconnected, and the hose plugged).