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Thread: tuning MAF w/STFT

  1. #1
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    tuning MAF w/STFT

    OK I tried the tune the VE with LTFT, but had better luck turning of LTFT and using short terms to dial it in with. I think I have one more run on another day with the VE and it will be perfect, with the changes I just made I should be within +1 - (-2), doing one more just to try and get even closer, if not this is good enough for me.

    Ok now the MAF question, I will use STFT since thats what I did so well with on the VE. So say my trim was +2 or so, on the MAF curve what value would I add to get that fuel to be added? Would I add .02 or 2 or how does this work??

    Chris
    2009 Silverado Crew Cab 5.3L, stock.

  2. #2
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    its % so you would copy the histogram, paste special & either multiply or multiply by 1/2
    It doesn't have to be perfect, it just needs to be done in two weeks...

    A wise man once said "google it"

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    kinda unlike VE then? On VE you get percentage in the histogram and the table is in percentage, so adding works on the VE table.

    I'm gonna start this MAF curve from stock so I might be a good bit off. I'll probably multiply by percentage on the first go and then do it by half the ones after that.

    Thanks for the help,
    Chris
    2009 Silverado Crew Cab 5.3L, stock.

  4. #4
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    btw, this is for a V8, i posted in wrong forum...oops!
    2009 Silverado Crew Cab 5.3L, stock.

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    works the same either way...trims are a % though so your multiplying not adding.
    It doesn't have to be perfect, it just needs to be done in two weeks...

    A wise man once said "google it"

  6. #6
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    ok yeah, multiply on the MAF. gotcha. I guess adding only works on the % vs. % tables. I'll give it a whirl, I should have my VE lined out and ready to reenable the MAF by the end of tuesday. Does anyone mind looking at my scan to see if it looks close enough on the VE?? heres my scan and file.....I have made one round of changes since this scan, havent logged yet.
    2009 Silverado Crew Cab 5.3L, stock.

  7. #7
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    a few things stand out to me...first being is this an open/closed loop hpt file and is the sd or not? Just some things are conflicting within the file like ect temp for closed loop enable...ses turned off for maf. Just not sure. Also damn thats a ton of low end timing...60* wow...your iat adder table is pretty conservative, you could probably take some of that out. Everything else looks ok i guess.

    lata
    Bill
    It doesn't have to be perfect, it just needs to be done in two weeks...

    A wise man once said "google it"

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    Senior Tuner S2H's Avatar
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    yeah...that spark table is kind of agressive..
    you should never be more than your Max torque reference table(and you should never edit that table)

    I use that table to build a new high/low octane spark table most of the time...but I also subtract a few degrees frm the whole table so I can get things more reasonable
    -Scott -

  9. #9
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    Sorry, its a MAF tune, I just have the damn light turned off right now because I am dialing in VE. I should have mentioned that. I havent started on the MAF yet. I will work on that spark table some, I'll try what soundengineer suggested on that. I'll let ya know how it works.

    Also, what should the ECT temp for closed loop enable be at? I left that stock, i havent touched it. I also set the power enrich MAP value to 112 so it wouldnt come on during my VE and MAF tuning and throw off my values.

    Chris
    Last edited by chrisj6; 12-12-2005 at 12:43 AM.
    2009 Silverado Crew Cab 5.3L, stock.

  10. #10
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    you should leave the PE turned on and just filter it out by using teh PID filter functions...
    [PID for fuel-air-multiplier]=1
    that will get you only results that are non PE
    and will keep yoru A/F safe where it need to be enriched some.

    closed loop enable should also be left at stock values if you are tuning using LTFT/STFT's
    -Scott -

  11. #11
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    ok thanks, thats where I left it, I wasnt sure though from foff's response if it should be any different.

    Chris
    2009 Silverado Crew Cab 5.3L, stock.

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    I copied the Max torque table over to my high octane and then to the low octane table today. Thanks for the tip! The truck is much more responsive and accelerates better on the low end part-throttle. I saw some KR when I did just a calibration write, so I did a full re-write and the KR hasnt come back since, so that will start my timing tables.

    Chris
    2009 Silverado Crew Cab 5.3L, stock.

  13. #13
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    the way I do it is based on best timing for the vehicle.
    I know that an LS1 f-body is in general best torque and power around 27* at WOT...so I just use the mak torque table and remove teh amount needed to get my table at WOT to the 27*...
    if it takes 4* to get there..then I take 4* from the entire table....
    and thats my starting point.

    this is very common practice on Fords and I figured it should apply the same to GM as well
    -Scott -

  14. #14
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    ok heres the new log and file after I am done with VE and used the max torque timing table to base my high/low tables off of. Also, I took some of the IAT adder out so its not so conservative. Starting on MAF tomorrow.

    Chris
    2009 Silverado Crew Cab 5.3L, stock.