[olddog]

The 50% - 85% is what I found when I looked at. 85% is just too hard to light to start a cold engine when it is below 0 F. They have to add more gasoline in the winter, and gasoline is usually cheaper, so you never know what the true blend is going to be from one tank to the next.

Some of the EFI tuning crowd have tried running E85 with the A9L box code ECU - which was 1989-1993 Mustang GT 5.0 manual. They have issues going lean and rich from tank to tank. I expect a Carb would be similar problems, but I do not know if the fuel molecule size differences would tend to help or make the issue worse. I think gasoline molecules are smaller and more would flow through a jet than ethanol. If true, then when you had more gasoline in the mix it would run richer, which is exactly the opposite of what you need. Sounds like a carb would be less tolerant than EFI.

If that wasn't the case, I would have switched to it myself. I decided to stay away based on others experience.