Forgive me for bumping this old thread, but this was referred to by unibomber in a newer thread, so I chose to share this information here.
Recently had an engine failure. Before the failure E85 was run for 7000 miles.(Not saying it was the cause of failure) During teardown I came across this,
Which I know is typical and was aware of this issue before switching to E85. (every injector looks this way)
However also looking into the intake I see this,
Its hard to see in this picture but there is a good amount of build up of this "gunk" all round the valve and in the intake. (looks like this for every cylinder)
Using a flat head screw driver i was able to scrape some of this "gunk" of the valve.
^This picture better shows the build up.
What was scraped off V
Now ive read many threads on evo forums and these forums about this issue, but none have I seen been this sevre. I suppose its possible there was an injector issue, but to see this in every cylinder im not leaning that direction. Generally used the same E85 station, perhaps they had bad gas or used diffrent conditioners/cleaners. However did test it one time, tested as a little better than e85. So I i'm not sure. Because of all this for the next build i'll be running an aguamist set up and regular 93.
All of this is just food for thought. I loved the power gain from E85 and the affordability. But I just dont think ill be going down that route again.