E-85 on a stock 370z?

Originally Posted by JeffP-Z

So I switched over yesterday to try and test. I ran the car down to as far on empty as I could, which was no longer registering a distance on the miles till empty, filled it half way with E-85 and drive about 50 miles, then filled it back up to full with e85. This car is running fine, except it threw a code (U0164 Lost Communication With HVAC Control Module, CAN Communication Error) which I am not sure is at all related. What didn't happen as I expected, the OBD2 never changed from fuel_type = GAS. I would have expected it to switch to E85, Ethanol, or similar. How does the ECU know I am now on E85 and not 93 to use the different fuel map? I have not had it tuned on E85, obviously, and will do it after my Berk test pipe arrives Friday and is installed. Just curious if this is a workable situation or do I need to get one of the E85 kits from Zspeed, CZP, or Z1?