e85 making the switch

[trashmechlv]

I have had several local Turbo Buick guys here convince me to try e85. They have been running it successfully for many years. I have a new e85 friendly fuel pump, 80lb injectors, AEM wideband. The new TT 6.1 chip is in the mail. Hopefully will be running by end of next week.  Buying the 110 fuel and O2 sensors has gotten old fairly quickly. Anybody here have their car running on e85? We are having a Buick "event" at the 4-25 test n tune so I will see how this car does on the new fuel.

[phil_long]

You'll end up upgrading your injectors I'm sure.  Most combos I've seen on the other board where damn near maxing out the 60's and the 80's with E-85.  Of course how fast you plan to go is relevant! Good luck and let us know the results!!!!

[trashmechlv]

I just bought the 80lb inj to replace my 60s. They are the biggest a stock ecm can run without being modded I believe. My goal is high 11s so they should be good. I will post some PL logs when the car is back running to see the inj duty cycles. Very curious to see how it compares to the 110 fuel.

[TURBOPOWERED68]

save your money and go straight to 120s
or continue to use ALKY injection to make up the difference.

E85 requires A LOT of fuel

[trashmechlv]

Got the car running on e85. Worked my boost up to 25lb and my wideband correction in my TT 6.1 chip is set at 10.8. The IDC was 80-85% at that boost level. Hard to believe $3.47gal fuel can run like that! Hitting the track April 25th to dial in and see what it can do. 

[Steve Wood]

Is the 10.8 the leanest number it runs without timing retard or is it an internet magic number?

Glad you got it going!

[trashmechlv]

The 10.8 is the default correction setting Eric set my new 6.1 chip at. I can change it for 1/2 gear and 3/4 gear. Im going to try and lean it out some and work on the timing now that its running well. The chip works well at holding the set AFR.

[Steve Wood]

I would not worry about the timing too much...seems boost beats timing almost every time

[trashmechlv]

Thanks Steve, working with the wideband is new for me so I am trying to start on the "safe" side. It seems the 80s will be enough injector for now.

[trashmechlv]

Here is my highest boost log. I have been seeing 1/2 shift knock occasionally even when I was running 110 fuel. This particular log was on street and was spinning tires bad through 1st gear and I peddled it once. I also have a question about the 02s as they are down 750ish at end of run but my WB reading was still rich around 10.8. Is that bad, does it need more fuel even though afr is ok? This is my first time being able to see the O2s and the wideband reading together as before I had no idea what my afr was.

Its hard for me to be able to go make pulls like this on the street around here, so I dont plan on hitting this top speed again until at the track. The knock at the shift kinda bothers me also, sometimes I get it and other times nothing. Any guidance is always appreciated! thanks

And I forgot to put my fuel psi gauge back on wiper before I went out early saturday. I checked pressure to boost rise through second gear earlier in week but not top of third gear. 

[Steve Wood]

I would not consider 10.8 rich when it comes to E85

Ethanol and gasoline have different stochiometric ratios and you are trying to compare apples and oranges. 

We have the same problem trying to define what is "lean" when looking at alky injection on a stock o2 sensor which is not only calibrated for gasoline but provides variable readings with changes in pressure and exhaust temperature...

[Steve Wood]

and if you want to further be confused.....r emember that .441 volt at cruise is stochiometric on gasoline on our stock sensor so anything larger than that such as .750 is considered rich....but not as rich as .800 which is bordering on "pig rich" but when cruising with relatively little exhaust temp and exhaust pressure, .020 v on the stock sensor seems to give me the gas mileage which is about 15.7 on the wideband sensor...and widebands are not supposed to vary much with temp and pressure.

On the other hand, E85 has a stochiometric ratio of about 9.8 altho I would double check my memory on that one...so one would not expect to see 15.7 on the wb for best gas mileage...

I prefer to find out what the car likes rather than picking numbers off the net...but, that's just me.  I like to tune.

[Steve Wood]

Oh, yeah, I tune with the knock sensor and add a couple % more fuel once I find the borderline where I cross into detonation...I like a little margin.

Whatever that reads on the wb band or the stock sensor at wot is my "magic Number" but it might not be yours

[Scoobum]

KR appears to be caused by wheel spin. I'd leave 3rd gear timing alone...now in regards to low gear timing...um... nevermind.

[trashmechlv]

Thank you guys. I guess I will work on it at the track on the 25th and see what way to go. It will be a prep night so my car should hook much better that night.