I use 91 octane and thats what i'm tuned for....

Now E85 is the "torque fuel" high octane rating of 105-106....

Theres a truck stop with 92 octane with 10% of ethanol...

Would this be better than straight 91 octane?

Obviously straight 92 is better than straight 91 but with the 10% of ethanol added is that gonna make the fuel worse than 91 or better?

Considering that E85 is 105 octane, and with the 92 with 10% fuel, means 90% 92 and 10% Ethanol....

So if you take 105 times .1 (10%) you get 10.5 and if you take 92 times .9(90%) you get 82.8....

Now if you add those it comes out to 93.3 octane right?

When i first saw the fuel it had ethanol in it and thought that made it have a less octane rating but that was months ago before i had my evo and now that i've read up on E85 i figure that this 92 octane with 10% ethanol would be a better choice then 91....

Let me know what you guys think?!

 

Yes, 93.3 octane is correct if you go with the 105 octane value for the E85. The problem for me to run that higher octane, leaner running fuel would be that you'd need a retune to get the total benefit of that new fuel.

However, if that fuel is only available in one service station then I wouldn't even bother to run it, as you couldn't travel far from home before having to dump some 91 gasoline back into the tank. Once you have the car tweaked to take advantage of that higher octane blended gasoline then you are pretty much tied to that one service station.

 

so as long as the ethanol part of the fuel is 105 its 93.3 but it will never be less than 92 for sure right? theres only one fuel station i go to for 91 and its the only one i know of in my town and the truck stop is 15 miles away in between my town and the town i work in so i drive past it 5 days out of the week so its no problem filling up there...but i really wanna convert to E85 i am gonna wait until winter is over to start getting the parts together to switch plus i need to talk to the owner/manager and find out with they every switch blends

 

The only problem with the blends is that it burns quicker than straight gasoline. most of the time it will have a lower pricer per gallon to make up for it. + 1 about getting it tune to take advantage of it. Here in SC, the stations that carry the 10% ethanol mix is plentiful.

 

Assuming that the fuel is consistent and the octane rating is listed on the pump, then you should be O.K. But, to take full advantage of the blended fuel you'd need to have your tuner reflash the maps for it. What is the price difference between your usual 91 octane and the blended fuel?

If your planning to convert your car over to E85, then I'd just wait. Two and a half octane numbers increase could make quite a difference powerwise as long as you get the car retuned though. If you don't intend to get the car retuned for the hybrid fuel then I wouldn't bother running the stuff.

 

well with that said i think i won't worry about the 92 w/ 10% ethanol....i'll just wait to switch to E85

 

Most of the time they actually use the 10% ethonal to raise the octane to their posted octane number. So it is still probably just 92.

 

True. They use the ethanol to help with "emissions"

http://www.northcountrypublicradio.o...tive-fuel.html