You absolutely need a tune for e85 exclusively. You can throw a few gallons in to fix some timing issues but I’m pretty sure you need to adjust ignition timing to keep your afr in range to run it exclusively.
E85 is rarely actually e85 so an ethanol content analyzer is usually required to adjust the ecu accordingly. It’s not just higher octane, all that does is allow for higher compression at a similar temp.
You absolutely need a tune for e85 exclusively. You can throw a few gallons in to fix some timing issues but I’m pretty sure you need to adjust ignition timing to keep your afr in range to run it exclusively.
E85 is rarely actually e85 so an ethanol content analyzer is usually required to adjust the ecu accordingly. It’s not just higher octane, all that does is allow for higher compression at a similar temp.