Number one; I have never heard of F-85 R and am ignorant of how it differs from regular E-85. Fill me in, please.
Number two, I don't race that much, so, I never buy 55 gallons of anthing at a time. Because I am still in a "tuning" mode and still learning (watching my A/F ratios, closely,) I still have the oxygen sensor installed and it absolutely won't tolerate any lead in the fuel, so, I have to buy unleaded racing fuel at about $10.00 a gallon. As you might imagine, that is not one of my favorite things to do... so, I am always looking for alternatives.
I don't know what A/F ratio would be recommended for E-85-R. For racing gas, under boost, it is 11.5:1.
Thanks for any information!:cheers: