That's an overly broad and potentially dangerous statement.
The ethanol is a definite benefit if you are *tuned* for it. The problem is, ethanol is less energy dense. When you tune for ethanol, you can up boost and timing, but you also have to squirt more fuel to offset the lack of energy density. If you just blindly throw e85 into a car that isn't tuned for it or built to adapt to it, you may wind up in a situation where you're getting plenty of octane, but your fuel pump/injectors/etc. aren't pushing enough fuel for your needs. Thats why e85 *tunes* exist, and nobody advises you to just throw e85 in and go.
You can throw a gallon of e85 into a full tank of gas and it'll raise the octane up a tiny bit/cool things off a bit, which the car's normal ecu will automatically adapt to. More than that, and it's outside the range of what the car can account for. The FiST is not a flex fuel vehicle, so you cannot run it on high concentrations of ethanol as-is.
The ethanol is a definite benefit if you are *tuned* for it. The problem is, ethanol is less energy dense. When you tune for ethanol, you can up boost and timing, but you also have to squirt more fuel to offset the lack of energy density. If you just blindly throw e85 into a car that isn't tuned for it or built to adapt to it, you may wind up in a situation where you're getting plenty of octane, but your fuel pump/injectors/etc. aren't pushing enough fuel for your needs. Thats why e85 *tunes* exist, and nobody advises you to just throw e85 in and go.
You can throw a gallon of e85 into a full tank of gas and it'll raise the octane up a tiny bit/cool things off a bit, which the car's normal ecu will automatically adapt to. More than that, and it's outside the range of what the car can account for. The FiST is not a flex fuel vehicle, so you cannot run it on high concentrations of ethanol as-is.
