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Thread: Stock LQ4/4l80 swap tuning help needed

  1. #1
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    Stock LQ4/4l80 swap tuning help needed

    I have a 93 obs rcswb with a lq4/4l80 swapped from an 01 2500hd truck. It feels lethargic and just boring granted, it has a 3.08 rear gear. I plan on changing it to a 3.73 in the coming weeks to hopefully help with that. I was wondering if anyone can give some opinions on things that can be changed to help pep it up a little bit, primarily the transmission tune. I'm not looking to do anything too crazy, engine and trans only have maybe 110k on them and both seem to run fine. I've put probably 30k miles on it since it was swapped by the previous owner. I'm completely new to tuning, I've changed a few things just from what I've seen from other tunes similar to my situation. Prior to me changing anything I compared the tune to the original from the repository and it was a direct match.
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    Last edited by ibinyth; 1 Week Ago at 11:14 AM.

  2. #2
    Senior Tuner
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    Quote Originally Posted by ibinyth View Post
    I have a 93 obs rcswb with a lq4/4l80, I've changed a few things
    save yourself a headache
    buy a turbo and be happier than a pig in a pen

  3. #3
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    Log cylinder airmass in scanner channels. Also MAF channels as well.

    Heres a tune just based on what you asked for and what the log showed. The air model was moved up an arbitrary 5% since LTFT+STFT showed about 10% lean. But its in blended mode, so those numbers are skewed...
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    "It'd be a lot cooler if you did."

  4. #4
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    Quote Originally Posted by horsepowerguru427 View Post
    Log cylinder airmass in scanner channels. Also MAF channels as well.

    Heres a tune just based on what you asked for and what the log showed. The air model was moved up an arbitrary 5% since LTFT+STFT showed about 10% lean. But its in blended mode, so those numbers are skewed...
    I uploaded the tune, I?ll have to get some good data logging but it seems to have helped. One annoying thing I keep dealing with is what almost feels like slipping. I dropped the pan a while back and change the filter and fluid. Saw absolutely no signs of wear, fluid was still nice and clean, filter looked good. I even added a dedicated cooler since it was running off radiator so eventually trans temps would just match the engine temp.

    It feels like a ?false neutral?, I?ll have to see if I can get a data log of when it happens. Not sure if it?s the transmission or the engine honestly. It just feels like power cuts out completely. Originally I thought it was because the TCC was never engaging. That was because the gear and tire size were completely wrong. That?s why I bought the hptuner in the first place. TCC was engaging at 65+ mph, but noticed on my little ecu scanner the vehicle thought it was just doing 45.

  5. #5
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    Not too sure why it changed all the ?s to ?s lol.