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Thread: advance always at 16? at any load

  1. #1
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    advance always at 16? at any load

    hello guys
    96 Vortec engine with 2002 Express file and PCM.
    stroker, intake manifold spacer, small cam, CAI, exhaust
    I don't understand what is gone crazy with the tune and calibration.
    I have idle advance working (even very few out of park only)
    but driving it's a flat line at 16?
    can you kindly help understand what is gone crazy?
    thank you
    SO MUCH!
    best regards
    Attached Files Attached Files

  2. #2
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    try disabling trans abuse

  3. #3
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    this one?
    what I feel very strange is that I have 16? constant regardless I go easy or hard with accelerator...
    abuse should kick in on heavy load, isn't it?

    trsabs.JPG

  4. #4
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    I would just rule it out first

  5. #5
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    was a problem with distributor not zeroed correctly
    BTW with the intake spacer the closest to zero with can go is about +10?... it's a pity but it works now and it run strong...

    but the injectors are not enugh at woth we are lean a bit and injector goes to 110% DC...
    any idea?

  6. #6
    Tuning Addict 5FDP's Avatar
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    More fuel pressure or larger injectors.

    No idea what those injectors are rated at but if you are only running say 43.5psi, bump it to 58psi.
    2016 Silverado CCSB 5.3/6L80e, not as slow but still heavy.

    If you don't post your tune and logs when you have questions you aren't helping yourself.

  7. #7
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    Quote Originally Posted by 5FDP View Post
    More fuel pressure or larger injectors.

    No idea what those injectors are rated at but if you are only running say 43.5psi, bump it to 58psi.
    problem is with FPR.
    on Vortech L31 is INSIDE the intake manifold...

  8. #8
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    I ran my GM MFI update spider at 70 psi in my Express van.

    If you cannot get the distributor CMR set correctly you may have it a tooth off.

  9. #9
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    Quote Originally Posted by Fast4.7 View Post
    I ran my GM MFI update spider at 70 psi in my Express van.

    If you cannot get the distributor CMR set correctly you may have it a tooth off.
    hello
    on the FP, how do you get the 70 psi? what parts did you used to reach that results?
    on the tooth, I can not rotate the distributor enough because of the intake manifold one inch spacer. I was able to "zero" at + 9?... any other idea?
    thank you so much
    best regards

  10. #10
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    Quote Originally Posted by Christian GM View Post
    hello
    on the FP, how do you get the 70 psi? what parts did you used to reach that results?
    on the tooth, I can not rotate the distributor enough because of the intake manifold one inch spacer. I was able to "zero" at + 9?... any other idea?
    thank you so much
    best regards
    From what I remember 1 tooth off is about 16?. If you are at +9, you need to retard the distributor 1 tooth.

    I had a GM MFI upgrade spider and the regulator had an adjustment screw on it. Stock fuel system, Delphi replacement pump with a Racetronix Hotwire kit held 70 psi with Zero issues.

  11. #11
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    Quote Originally Posted by Fast4.7 View Post
    From what I remember 1 tooth off is about 16?. If you are at +9, you need to retard the distributor 1 tooth.

    I had a GM MFI upgrade spider and the regulator had an adjustment screw on it. Stock fuel system, Delphi replacement pump with a Racetronix Hotwire kit held 70 psi with Zero issues.
    good to know, not easy to reach inside the upper intake manifold but good to know. need to adjust clockwise or counterclockwise? 1 turn? more or less... don't want to remove and reinstal the mainfold too many times
    I've the Taylor Cable 11011 Vmax Intake Manifold Spacer and this prevent the distributor to set as needed due to interference issue. if I clock one tooth I go to - 20? and it is worse.
    any idea to set to zero will be appreciated
    merry Xmas!!!

  12. #12
    Advanced Tuner IARLLC's Avatar
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    Your fuel pressure is probably at at least 58-60psi already as the earlier spiders would not start (not able to force open the sprayer) at less than that. If you already have the updated set-up with the injectors moved out to the tips it might start at a lower pressure. Just saying that your pressure is already at least 58....but might be able to for the injectors still by getting up to 70.

    10 is within GM's parameters. You could run with that but I think the -20 must have been 2 teeth back. It might be worth trying again to get closer. The code that gets set if it is too far off is really a protection for the cap & rotor/performance. If too far off the spark will have to jump a gap between the cap and rotor which eventually burns out the cap and of course weakens the spark at the energy available at the plug.

  13. #13
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    Quote Originally Posted by IARLLC View Post
    Your fuel pressure is probably at at least 58-60psi already as the earlier spiders would not start (not able to force open the sprayer) at less than that. If you already have the updated set-up with the injectors moved out to the tips it might start at a lower pressure. Just saying that your pressure is already at least 58....but might be able to for the injectors still by getting up to 70.

    10 is within GM's parameters. You could run with that but I think the -20 must have been 2 teeth back. It might be worth trying again to get closer. The code that gets set if it is too far off is really a protection for the cap & rotor/performance. If too far off the spark will have to jump a gap between the cap and rotor which eventually burns out the cap and of course weakens the spark at the energy available at the plug.
    right now it is about 50-55 psi not more, with already installed new style spider... better I found a way to rise that pressure, is way too lean at WOT
    tnx

  14. #14
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    Quote Originally Posted by Christian GM View Post
    good to know, not easy to reach inside the upper intake manifold but good to know. need to adjust clockwise or counterclockwise? 1 turn? more or less... don't want to remove and reinstal the mainfold too many times
    I've the Taylor Cable 11011 Vmax Intake Manifold Spacer and this prevent the distributor to set as needed due to interference issue. if I clock one tooth I go to - 20? and it is worse.
    any idea to set to zero will be appreciated
    merry Xmas!!!
    Take the upper plenum off. Reinstall the fuel lines. Jumper the fuel pump relay to make the punp run. Set your WOT pressure to your liking. Reinstall the plenum when you are done. At 70 psi you should have fuel for about 400-420 hp. Should end up about 24.5 lb/hr flow rate.

  15. #15
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    I have this style
    no screws at all, so I removed the small screen, with a small socket and hammer I hit in the middle the FPR.
    this way I preloaded the spring, tested a couple of time, 5.0 BAR exaclty
    just to share the info for anyone who needs
    bye
    fpr.JPG