I only mention the “cold start issue” because they adjust the fuel to try and help it along. I know of two guys in eastern PA that had fits with it into late May this year because the change over is not clear cut (station fill to station fill), and then there is at least some speculation that they are over 15% gas a lot of the time (when they don’t have enough alky available). Possibly not a show stopper for you, but ran me away from it for now. Keep in mind the bulk of the E85 market is intended to offset gas usage, and they arent real concerned about those of us looking to it for octane. (more gas = less octane).
I’m not sure how the strategy is set up in the Mitsu stuff, but mine will not compensate enough for the fuel differences at WOT / high load situations. It can be tuned for closed loop, but above 3500 rpm or a specific load value I’m in open loop and running off tables only, so that is what stopped me. Without know what the fuel make-up is, I could never get the tune “right enough” to take advantage of the octane.
I keep watching others conversions myself, I tend to follow these types of things once the kinks are discovered rather than pioneer myself on something like this. I still hold out hope someone is going to make a more stand alone / affordable fuel ration sensor we can plug in to make this easier.
Good luck if you go this way, I will be watching for your results too.
Bob Myers