Back to this thread for a second.... Even if the fuel system can handle it, I wonder if too much E85 could hurt performance? My Continental fuel system can handle all the E85 I can throw at it. I am the running the 4th revision what Brad is calling an E50 tune. Our latest revision looked the best on the logs and feels very strong but I was probably only running about 35-40% ethanol when we logged it. Boost and timing looked good to Brad.
I carefully refueled to get a 50% mix and took it to the track but car was slower than it was with an earlier version when I was running a lesser E mix. Could too much octane (burning more slowly) hurt performance if timing is maxed out?