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Let's play, "Plug in the numbers".

Posted by v8s_are_slow, Dec 11, 2013

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  1. v8s_are_slow

    v8s_are_slow Proven Member

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    Joined Sep 30, 2002
    Panama City, Florida
    Posted this on the Link forums but figured I'd get more replies over here. Accidentally posted up the Lite version of this though. Oops, but basically the same thing really.

    So I was talking to Drew Jones about this earlier today during my lunch and was wondering how people get the numbers for their Octane tables. Not the obvious stuff like idle and wot. But the stuff that's inbetween. So figured I'd post it up here as well since I didn't have a lot of time to talk to him about it, and see what different people have to say.

    I've taken the "Stock Evo8" table and lowered everything to like 8.0 I believe, that's not either 14.7 or 10.1 in the table. So if you see an 8.0, that was a different number than what you see, and should put in what you feel should go there. Now I saved it as a log after doing this and figured I'd post it up and see what others come up with. Don't cheat and look at the table in the wiki. Just put in the numbers that you think should be there, or at least tell us why you're doing it, or why it wouldn't be possible. If ya do it, save the log and post it back up on here.

    For me, some of it just doesn't make sense. Have a look. See where the 10.1 kinda jumps around? Now look at the next one.
    Pluginthenumbers_zps7c04a19e.gif

    This is what I would "think" it should look like for the wot section, but still not sure about everything that's an 8.0 number. And wondering why the first column isn't 14.7 for the idle. Personally, I've taken a guess when tuning between idle and wot, but feel there's a better way that I just don't know, and that's what I'm trying to learn.
    Pluginthenumbers2_zps7c36b996.gif

    So let the opinions begin, or post up your version of what it should be. Thanks!

    Guess I'll post up the stock Evo 8 map for those that can't access it, but still wondering how you would come up with all the numbers between 14.7 and 10.1 afr's.
    StockEvo8_zps49f4c340.gif
     

    2K  20

    1998 Mitsubishi Eclipse GST
    10.949 @ 129.77 · 2G DSM
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  2. Phantom DSM

    Phantom DSM Proven Member

    540
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    Joined Jan 28, 2007
    Dallas, Texas
    The Table does not have to be perfect with streamlined numbers. As you go down and further right with high rpm, the ecu will use that point to reach the A/f r.You will notice that the ecu rarely if ever uses the 1.4-2.6 cells under 1250 rpm, who would boost up at that point... If you right click at a certain cell on that table, you will notice the option to "interpolate". It will average out 4 surrounding cells and will make it more seemless and transitional.
    Also if you click on a log point and access the openloop max oct table, sometimes it will show up to 4 cells highlighted, which means the ecu took an average to determine your desired A/fr. The same usually happens on the VE table.
    You can choose desir a/f ratio and average out the table if you want to make it look seemless. There is a lot more to this, im only generalizing. I hope more knowledgeable people can chime in if my post does not explain well.
     
  3. v8s_are_slow

    v8s_are_slow Proven Member

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    Joined Sep 30, 2002
    Panama City, Florida
    Forgot to post the log. Sooo past my bedtime. Ugghhh...
     

    Attached Files:

    2K  20

    1998 Mitsubishi Eclipse GST
    10.949 @ 129.77 · 2G DSM
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  4. Phantom DSM

    Phantom DSM Proven Member

    540
    10
    Joined Jan 28, 2007
    Dallas, Texas
    Damm i can't check the log, using a diff laptop right now. I see what you mean now, i thought we were discussing the cell numbers in general. With a log it is more useful to select the points to adjust and then streamline the surrounding cells so that there is not a harsh transition for the ecu.
     
  5. fwbt

    fwbt Proven Member

    70
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    Joined Dec 31, 2007
    Raeford, North Carolina
    You're a bit off in the WOT and idle ideations. During closed loop (Idle) operation the ECU uses the O2 sensor to monitor the fuel trims in order to achive a 14.7 AFR. Now for open loop (WOT) operation it uses that table to achieve the AFR's that are specified by making and educated guess on the amount of airflow entering the engine based off the MAF (or simulation of MAF). Now open/ closed loop is like an on off switch, either it is or isn't in one or the other. Like Phantom said there's a bit of interpolation between the cells, it makes an educated guess based on the between values of the cells. No different than a MAF would between Hz.
    There's a degree of common sense in the tables though. Here's an example, say your O2 sensor just goes dead while driving. It happens. so instead of basing to a straight low (8.0) AFR it's going to think it's a light load, decent/ low RPM and try to keep the AFR's around the map based on how you're driving, so you don't just dump straight gas on the ground. (or explode your engine) As for the first column, your ECU isn't in closed loop when it first starts up, so it needs a fairly justified point to idle well.
    As for making power depending on the load level and RPM it may not be best to run a 10.1 AFR. Running leaner creates more power at a cost of detonation and heat. At a certain point it becomes advantageous to use fuel to control the incoming charge by introducing more fuel and using it to control detonation. All that plays into the specific characteristics of the map itself, if you wanted to fine tune it you may find a you can get away with a small increase in the AFR's in order to increase power.
     

    Street Build 2K  0

    1990 Eagle Talon TSi AWD
    manual · 1G DSM
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  6. lil corb

    lil corb Proven Member

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    Joined Sep 7, 2005
    Woodbridge, Virginia
    For someone who is in the process of maf calibration using the wideband. How do you know what cells to set your new target A/F of without doing a pull? Would be bad to just make everything 11.1 for instance as you enter WOT?

    In this example using the EVO8 A/F settings, would I leave everything that's not lower than 11.1 alone and just raise anything lower than 11.1 (i.e 10.9 and lower) to11.1 then do a pull and fine tune by cell tracking? Then after that look at wideband factor % at the different Hrtz points to calibrate?
     

    Attached Files:

    Drag Race Build 1K  0

    1991 Eagle Talon TSi AWD
    13.2 @ 103 · 1G DSM
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  7. v8s_are_slow

    v8s_are_slow Proven Member

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    Joined Sep 30, 2002
    Panama City, Florida
    Just to be clear, the log posted isn't something I used in my car or even plan to. It's just the Evo 8 stock settings that I copied. My intentions were to zero out everything that wasn't either a 14.7, or a 10.1, however the only thing I could do was lower them all to 8.0.

    Sooooo, what I'm asking people to do is to change all the 8.0 cells to what they think it should be, and then tell us why you think it should be that way. How did you come up with this decision.
     

    2K  20

    1998 Mitsubishi Eclipse GST
    10.949 @ 129.77 · 2G DSM
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  8. v8s_are_slow

    v8s_are_slow Proven Member

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    99
    Joined Sep 30, 2002
    Panama City, Florida
    I think I've posted the most difficult question for anyone to answer. Cause I've posted this on 2 different forums, I've asked lots of different people, and I've yet to get an answer on this one. Lots of scientific lingo, but no answer. Lol. Must be a big secret in the tuning world.
     

    2K  20

    1998 Mitsubishi Eclipse GST
    10.949 @ 129.77 · 2G DSM
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