kcjaz
SILVER Star
As always, “better” is in the eyes of the beholder. I agree that ethanol free isn’t generally economically better based on price per gallon or per mile. I’ve measured my fuel economy and ethanol free gives me 1.5 to 2 mpg better. With my aux tank, I have 48 total gallons which means about 70 to 90 miles more range. That’s my “better”. Pricewise in KC, it’s generally a wash or if you have to buy premium to get ethanol free, less economic.Except it isnt. Using a lower octane in a higher compression engine will result in knocking and eventually failure.
Now for same octane rating, there is not much difference. Gallon for gallon, ethanol free delivers 100 units, while E10 delivers 96.6 units of energy.
How much of a premium are you willing to pay for 3.4 units of energy? It is easy to do the math to see if it is a bargain, but most ethanol free pumps are overcharging significantly for that extra 3.4.
85 octane isn’t generally a choice except in places like Colorado and Utah. I would not choose to run 85 in my 200 but have when I had no other option. I didn’t notice any knocking or issues with it. Running 85 long term probably isn’t great for a 200.
I don’t think 87 vs. 91 makes any real difference in a 200. Others will disagree and that’s fine. I could be wrong. I just do not hear any difference, see any mpg difference, or feel any power difference. I do fill up with premium if I’m going to not drive for a few months over the winter because I believe the additives are better but I have no science to back that up.