Octane is only the rating of resistance to detonation (the higher the octane, the more you can compress the fuel before it explodes).

The correct stoichiometric ratio for regular unleaded gasoline is 14.7:1, while 9.7:1 for E85 (and can be any value in-between for different alcohol/fuel ratios). In newer cars, this means either holding the injectors open longer to get extra fuel into the engine, or running a higher flow rate injector. I don't know if your injectors and/or computer can compensate for E85. It might be a question for the Mopar performance guys.

Bob
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