Considering an E85 Experiment

[Allch Chcar]

The O2 sensor operates on Lamba so you use the same AFR values as Gasoline. The true AFR values are different but the O2 is just feeding converted values for Gasoline.

That's interesting about the conversion. I'm looking to do that once I get up and running.

[Ladogaboy]

Yeah. My main concern is that my fuel delivery system won't be able to keep up enough flow of E85 to maintain the lambda settings. I'm thinking, though, that as long as I drive normal for street (nothing more than 200% load... which doesn't happen often for me anyway), I should be fine.

Of course, I'm also wanting to adjust my current tune to maximize the usefulness of E85. I have an expert in the field (my car + E85 + tuning) whom I will want to consult, but I might also see if some people here would mind helping me see if I can mimic an Atkinson-cycle for my engine at cruise loads.

[Allch Chcar]

If you're looking at Atkinson cycle, that's a whole different topic. And we do have a discussion about that. I haven't checked on it lately though.

I still can't believe you're considering experimenting on a new car. If you're going to do it, get it tuned by an E85 guru. Don't risk your engine.

Originally Posted by drmiller100

first, ethanol is lighter then gasoline, and injectors inject via volume, and stoich is normally measured by mass.

Ethanol is infact heavier than Gasoline. Being 33% oxygen makes it heavier and reduces it's energy density. It's also what makes it so energy efficient.

[Frank Lee]

Risk is slim to none if one eases into it with increasingly stronger blends, noting any effects along the way.

[Allch Chcar]

If he keeps it in closed loop. The base map for Open loop is based on absolute values though.

[Frank Lee]

Doesn't change a thing I said.

[roosterk0031]

Just start mixing already and log the results. Once down 100 miles top off with E85, first tank will be e20ish. Come next refill put in 8 gallons E0/10 top off with E85, calculate the E% and just keep on going. To really test if your fuel pump & injectors can keep up you'll need to do a run or 2 after it's adjusted the fuel ratio and can supply enough fuel. I'm guessing good to E50 after than might get a CEL.

[ZR1-S10]

I've started trying stronger blends in my 96 4.3L S10 now too. I easing into it very slowly. Just filled up with E14 I'll let you know how it goes.

[SOUL-DRIFTER]

I use to run E85 in my 1994 Ford Aspire.
As long as the price difference was 62 cents or greater it was worth it.
I dropped 6-8mpg running with it.

[ZR1-S10]

Well one day in with a scan tool.

My live data shows VS 87 octane "winter tune"

Closed Loop
Coolent temp 165* F
IAT 79* F
Timing adv. ranges from -42.5 noload to +10 WOT
Short Term Fuel Trim -5 to Long Term Fuel Trim +16


It will be some time before I get cal. a difference in mileage