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Testing E85. Do you?



It is much easier to do it that way^^ than changing stoich.

There is a ton of stuff that needs changed in addition to the stoich table if you are choosing that route.
 
It is much easier to do it that way^^ than changing stoich.

There is a ton of stuff that needs changed in addition to the stoich table if you are choosing that route.
If going this route, will the wideband still read the same as it would for 93 octane?
 
This may be taking the thread off track a bit, but I think it might be worth it, so her goes;

Stoich vs. Cylinder gain....

Iv'e seen a couple times here and there that this method is better than that method, or that way is easier than this way.... As someone who is just beginning tuning, and not really married to one method or another, what I would like to see is factual arguments on why one way is better than the other. Also, where one method falls short compared to the other.

Why do you believe you method is the "better" way?
 


And I have laid out my explanation as well. And you have the link for 97autovettes writeup. As indicated both methods work. As for my reasoning, well your changing stoich of the fuel so why fudge another table fnot something that never needed adjusting?
 
Not really and it's already been proven

I ran e85 for a bit using the stoich option to change it. You need tiny tuner to make all the changes required. Changing cylinder gain, or IFR, you only need to change that one table. Way easier to leave stoich alone.
 
If going this route, will the wideband still read the same as it would for 93 octane?

You can either run the wideband like on 93 and tune for 11.5 or whatever at WOT, or switch it to e85 and run it at 7.8 or whatever it should be.
 


So what happen when you swapped stoich values in the master stoich table what happened? Did your afr go back to 14.7 anyway?
 
I think my tune is pretty happy. Running 100% original GM maf table for the 4" truck maf sensor from zzp and 100% correct injector offsets and flow rate. WOT fueling is commanding a static 10.8 commanded afr. Fuel trims are within 5%. Only hacked table is the cylinder gain set to 1.2. Here are the results. Keep in mind this is running winter blend E85 (So actually e70) and a gas calibrated wideband.

 


IIRC, you said you were running 60lb injectors?

So your IFR table is "60" across the board? No change per manifold vacuum?
 
Set to 63 across the board. The flow-bench balanced them all out at 63 so thats what I run. Only other fuel system stuff is a AEM 320lph E85 pump. (Im a big fan of using math and logic to tune. Although I have a great talent for educated guessing when I need to. I once modded an entire maf table with only 5 minutes of driving and two wot pulls sent to me in a data log to tune off of. The entire table was within 6% fuel trims when the guy flashed it :P)
 
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If you're running a return style system than regardless fu El should be flat across the ifr table. Return less style are gls generally a upward slope.as stated above
 
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