So I live in Utah county, the two shops I purchased non ethanol premium, now only sale 88 with no ethanol. What is better for the stock sled, 91 prem. with ethanol or 88 no ethanol?
Ethanol free 88, or 91 with ethanol
- Thread starter goforbroke
- Start date
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mike_s
Well-known member
Ethanol is actually a high octane fuel in itself, but it takes more of it to reach stoichometry. If your engine requires 91 octane rated fuel, then that is what i would run, but the ethanol blended in will lean the mix slightly, and it is more suceptable to separation. The etanol will come out of suspension over time, so dont let it sit long. Perhaps one could get away with running the 88 and some octane boost if you are leery of the ethanol blended fuels.
This is what I am doing, except 1 gallon of race fuel or av gas and 9 gallons of 88 per tank. I feel my engine needs the extra octane because the manufactures are running them so lean in the mid range they are more prone to light deto. The race fuel part isnt a big deal to me since I have it around for my turbo anyway, the only down side is it costs a little more.
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mike_s
Well-known member
I bet if you figure in the price difference of the 88 vs 91, then add in the cost of the 110 (or whatever the rating of your particular race fuel or aviation fuel) the price difference isnt really all that much. If i was in either of your two situations, i would probably take a route similer to this. Seems the best way to get the octane rating you need without the ethanol and the problems it brings.
silver eagle in Heber
I tend to ride up Lake Creek so it is on my way. I like to avoid ethanol, but with a head on and I already have to add race gas for deto below 9000 feet, I will have to use 91 with ethanol now. Just looking for people opinion on what is best for my stock 13 pro. I'll likely run 91 with ethanol as it cost less and has higher octane. Wish 91 without ethanol was available.
