your looking for spark blending, got it.
no there isnt a spark blend table in this OS. From what i remember in testing you select the Ignition for E85 and it has been assumed that the ignition is linearly ramped by percent of alcohol from table A to table B. (A being High Octane table and B being Flex Table)
you will have to track content vs main spark and map it against a linear blend curve that you make yourself using the High Octane and E85 tables to see how the linear blend factor is programmed in. The early computers can handle E85 but they do it with very crude basics as you are now finding out. Below is an example of the linear relationship between high and E85 tables in a bogus example where High octane cell would be 14* advance and E85 in the same cell would add an additional 12* for a total of 26* at 85% content threshold. i didn't test if the table was set to considered 100% blend or 85% blend the max content.
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