How much of an effect will oxygenated winter fuel have on AFR??

 

Stay away from that **** as far as you can. Here, let me rattle your brain.

First off, stoich for pure E10 is 14.13

The problem is that we do not know if your gas is pure E10 or if it's really E5, E6, E7....

So this brings up the problem of should you change your stoich from 14.68 to 14.13? Should you put it at 14.3-14.4 to compensate for the fact you don't know if it's exactly E10?

Let's say you do change the stoich. You'll have to go back and change your PE ratio of course using the 14.13 lambda. What about your narrowband sensors? Are they going to be able to adjust to 14.13 without any issues? Will switch points have to be changed?

Don't support the enviro-hippies and just run the regular gas. I live in MN and they try to shove that **** down our throat. I put the non-oxygenated snowmobile and motorcycle gas in my truck

 

You could always purchase an ethanol test kit to find out the exact % of ethanol in the fuel. They are relatively cheap, got mine for about $25.

That's my only option in my area is ethanol blended fuels so I got myself a test kit and I adjust stoich accordingly in every tune I do for whatever % of ethanol is in the fuel as that is the correct way to do it.

Most stations in my area year round winter or summer have about 5%-7% ethanol.

 

Changing the stoich value for e10 is the ONLY thing that needs to be changed in the tune, power enrichment, switchpoints and everything else should be left alone. If the tune is done right in the first place then everything else will fall into place with the change in stoich.


Narrowband sensors will keep fueling centered around a Lambda of 1.00 no matter what type of fuel is in the tank whether it's e5, e10, e85, pure gas it doesnt matter.