E85 and 91 mixture??

[SVT Ryan]

I only get 91 in my town but we have a e85 station as well. Can you mix the two together to get a higher octane on the stock fuel system to get say 93? I used the calculator and it came out to e25

 

[Carbd86GT]

I don't recommend mixing it, not that you can't do it, but you will never have the mixture the same as the time the tune was made. I just think it's kind of chancing it if you can't get the mix right all the time. In your case, I think I would stick with one or the other, you won't gain much going from 91 to 93 octane.

 

[me32]

Do not mix 91 an E85 if your are running a 91 tune adding E85 will lean it out.

 

[04sleeper]

As Carbd86GT@Lethal mentioned. You would have to have the EXACT same amounts each time you fill up in order to keep your A/F the same.

This is why it is difficult to mix fuels.

But if E85 is available, why not just switch over 100%?