Reverse Tuning E85

I have been thinking on this for a while and wanted to get some feedback on the idea.

The typical approach with E85 tuning is to first to the car for 93 octane (or whatever octane is available) and THEN tune the car with scalars for E85. The higher resolution map is 93 octane and then that tune is being changed based on Ethanol content and ignition timing is being added along with boost.

What if

You tuned your original map from the start on E85. And then used scalars to remove timing and boost pressure when the lower octane 93 was detected. I drive my car 99% on E85 and basically on use 93 if I am in a pinch and need fill up when there is no E85.

It seems to me that it would make more sense to have the main tune be for the most used fuel type.

That being said I am not a tuner… Thoughts on this?

No problem at all you just remove the amount of % change in the fuel map and do a new ignition map on 93 octane your done .

Is it better than the traditional approach?

If your e85 map already done than just pull some +_ 30 % change out of it chk the afr and your done .there is nothing wrong with it if you start on e85 first.

If you are predominantly running on E85 then yes it would make sense to perform your main mapping on that particular fuel. There isn't really a 'right' or 'wrong' way to approach the tuning and a lot will come down to the specific capabilities of your ECU and how it deals with flex fuel support.