Thinking of going to E85 on the Dart

As we are installing my 408 in the Dart, we are talking about the need to use race gas or adjust the timing when using pump gas. The thought is that using pump gas and dialing back the timing could bring me closer to 400hp rather than 500hp. Tom has a buddy who does an E85 changeover that involves rejetting the carb and a few other things. Tom tells me one of their race cars is set up that way. It has 105 octane, costs less, and would keep me from having to change timing all the time, giving me full power capability at all times. I could drive to the track and run on the same tank of gas. Plus it runs cooler and is available anywhere. Has anyone tried this yet? Anyone heard any feedback? I am leaning this way. I didn't put this motor in to have it detuned to run on the street.