Question about power curve with ethanol enabled.

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Fair enough. I thought the method by which the power is added is by advancing ignition timing beyond which lower octane fuel allowed because it would knock... so that the pressure reached the piston closer to *just* after TDC and not later.

I didn't know there was something outside of the one table that affects how ignition is advanced based on ethanol being added. I know that table works in conjunction with another that has the ethanol % to determine how much of the ethanol ignition table number gets used and applied to the base ignition table... or whatever it's called (don't have Ktuner program open in front of me right now).

Just trying to learn. It seemed that there more going on beyond the ethanol ignition table alone since there was a substantial amount more power below where that table would seem to do anything and was trying to figure out the method by which more power was being generated. I'm in it for the knowledge. Thanks.
A will to learn is always a great thing. Before you go much further with your analysis I’d recommend confirming that the dyno results that you are looking at came from the tune you are looking at. (assuming you have not already) Otherwise it’s apples to oranges.
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charleswrivers

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You do, in fact. Knock Control. :) We talk about it all the time.
Oh....

Now I feel stupid. Because K.control isn't moving... it's letting the base table not get knocked down because K.control is rising. The the ethanol table is there, along with the other percentage table to dynamically add the timing on that table based on actual ethanol percentage since... well... that's was the whole purpose of the ethanol sensor... not having to be locked down to one ethanol tune and being to mix whatever and it just work.

Makes sense now. I hadn't come back to K.control staying bottomed out because you weren't knock limited anywhere. Lightbulb. Makes sense now. Thanks @KTuner.
 
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charleswrivers

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A will to learn is always a great thing. Before you go much further with your analysis I’d recommend confirming that the dyno results that you are looking at came from the tune you are looking at. (assuming you have not already) Otherwise it’s apples to oranges.
My question had come from looking at the dyno provided a gain of ~50 ft-lbs of torque gained below where the ethanol map provided any timing advance and was trying to determine the method by which gains were made with nothing I saw on a table. Just trying to learn the effect of ethanol, beyond the table alone. I just got my answer that seems to tie it together. In my mind anyways.

Yeah... Without a dyno, is dont see how you'd ever really find your actual peak power point and not risk exceeding it it where the pressure if reaching the piston at or (shudder) before TDC if you weren't knock limited. There things e-tuners know from Dyno tuning that they can apply to e-tuning that the casual/amature/idiot guy (which I am) messing around with his maps doesn't know and can certainly get him into trouble quickly.

I still was interested in what was going on... mainly based on me not wanting so much torque down low on my car. I'd planned on countering it... but there was no ignition to pull off the ethanol adjustment table to do that. It's have to be with limiting boost, I suppose.
 

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Along with all that, and dare I throw out a possibility without knowing for sure, but perhaps he started a hundred RPMs earlier in the run. A human still ran the vehicle and 100% repeatability is never 100% possible.
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