I have an SCT x3 from mike @ 5 star with 87 econo, 87 perf and 91 perf. I havent been able to find 91 octane ANYWHERE in my local area... would it be ok to run 93 octane or should i just see if i can swap out a tune with him somehow?
Thanks!

 

You are ok running a higher octane fuel than the tune you have in but you dont want to run a lower octane fuel then the tune you have , With a lower octane you will get bad pinging

 

Cool, that is what i figured but i wasnt sure. Is 91 straight gas and no ethanol?

 

Not real sure abt the ethanol I think different stations have different standards on the use of ethanol, It seams like the further west you go you run into more ethanol....

 

Yeah, out here basically every station says 10% ethanol but its probably more

 

Higher octane does NOT mean lower ethanol. Oil companies are only allowed to use no more the 10% ethanol in the gas. Every state has different laws as the way they let you know how much is in the gas. Here in MI they do not have to post it, but in FL they must post it on all gas pumps. Finding pure gas is rare and will cost you more. There is a large thread in the F150 forum about that topic if you would like to read. https://www.ford-trucks.com/forums/1...-ecoboost.html.
But higher will be ok to, if you really are still unsure you can call Mike and he would let you know for sure.