Ford Focus Forum, Ford Focus ST Forum, Ford Focus RS Forum - View Single Post - What octane fuel to use?
View Single Post
Old 10-31-2012, 12:55 PM   #19
Where am I?
zetecDon's Avatar
Join Date: Feb 2009
Fan#: 62506
Location: east of Cincinnati, OH
What I Drive: 02 MX-5 and 09 Focus Coupe

Posts: 9,343
Points 14,869, Level 79
Points: 14,869, Level: 79 Points: 14,869, Level: 79 Points: 14,869, Level: 79
Level Up 4% Completed
Level up: 4% Level up: 4% Level up: 4%
Forum Activity 16%
Activity: 16% Activity: 16% Activity: 16%
FF Reputation: 30 zetecDon Great Standing Member
Buy-Sell-Trade Rating: (50)
Originally Posted by Fan4Focus View Post
I don't claim to be an expert on this subject but, I will say I have ten years of experience with using a blend of E85 here in Minnesota with no negative effects at all and I DO see a gain in mileage and performance. You can listen to all the negative information out there about ethanol or, you can take it from someone with experience. Just understand, I am not advocating that anyone run full E85 in a non flex fuel vehicle. That WILL create problems with your system. I am only suggesting a 20-30% blend,

You are correct that the ECU makes very quick adjustments to the fuel/air mixture. What happens with the ethanol is that it sees it as a lean mixture due to the higher oxygenating effect of the ethanol. The computer makes big adjustments to compensate for a lean mixture, hence the possible drop initially. Then the ECU makes much smaller adjustments over time to get to a balance. That is why you may initially see a drop but it will stabilize after a tank or two when it sees this as the new normal. The ECU does learn or driving habits and compensates accordingly.

I will drop the subject at this post. I know I am in a small minority of people who have long experience with ethanol.
Tom wasn't trying to cast you out here. He was just merely stating the fact that he has seen performance runs on a dyno when people are using E85. I know a few people who have ran E85 also. They get mixed results varying on where and when they get it. Just because you have some experience on it does not make you an expert on it by any means. As Tom and I have said before, there really is no regulation on E85. That means you can have an octane rating of 102 one day then the next delivery will be down around 82 octane. The only thing I would suggest to someone is to read up and learn as much as you can about E85 before even attempting to use it.
zetecDon is offline  
    Reply With Quote