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Thread: brain fart, LSA, hitting hard set limiter at certain power level

  1. #1
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    brain fart, LSA, hitting hard set limiter at certain power level

    Might be related to modeled tq output I was thinking, but modding VTT and keeping it under 1000ft lbs didnt seem to do anything productive. Dont SEE it closing throttle percentage, but it just shut down mid pull hard hitting a brick wall. I do notice timing jumping way UP when it happens. Is there a cyl/airmass limit at 2.0 gms/cyl I dont recall having issue with one on these ECU unlike some C5 vette stuff. Nothing SAYS its limiting, Tq management Type all 3 say none, Throttle Desired stays 100%

    I can literally put one more # on the gate and itll cut it right as it spools up. Run7 doesnt do it, run17 does. ETC Limits in all gears maxed, Max Torque in all gears, Spark Tq and Throttle Torque disabled, in Tip in Limits ETC and Torque Limit2 disabled no change to how it acts with 1 more psi
    Attached Files Attached Files
    Factory Stock 97 SS M6 13.51 @ 104.3 mph
    Stock Longblock LS1 w/ 233/238 P.S.I. Cam
    10.81 @ 126.9 Full interior, six speed on 275 radials, a decade ago

    '99 TA trunk mounted 76mm 6 Liter
    9.0s in '09 @ 153 MPH

    Turbo 5.3 Volvo 740 Wagon
    32psi and still winding out 5th on the highway somewhere

  2. #2
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    Any ideas?
    Factory Stock 97 SS M6 13.51 @ 104.3 mph
    Stock Longblock LS1 w/ 233/238 P.S.I. Cam
    10.81 @ 126.9 Full interior, six speed on 275 radials, a decade ago

    '99 TA trunk mounted 76mm 6 Liter
    9.0s in '09 @ 153 MPH

    Turbo 5.3 Volvo 740 Wagon
    32psi and still winding out 5th on the highway somewhere

  3. #3
    Advanced Tuner PGA2B's Avatar
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    Did you adjust the Boost Disable?
    2013 OBM A6 CTS-V Coupe
    Mods: Headers back Billy Boat Exhaust, GripTec 2.65, 8.6 PowerBond Lower, LSX Innovations Solid Isolator, ID850's, NGK TR7IX's, Accel 9070CK Wires, Spectre CAI, SRI Ported Throttle Body, SRI Catch Can, NGK AFRM, 160* T-Stat, 0fx2gv Brick, Hard Line Delete W/3/4" Lines, FB 101 FMIC, Pierberg CWA50, Stoptech Drilled/Slotted Rotors, EBC Redstuff, Cut Stock Springs, Flat Bottom Steering Wheel
    2006 Black Raven STS-V (Traded In)
    Fully Modded: 459RWHP@5888rpm/451lbft@4696rpm

  4. #4
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    Quote Originally Posted by PGA2B View Post
    Did you adjust the Boost Disable?
    This is turbo setup. Supercharger Torque Management switches are all set to disable. Does anything in Engine-Torque Management-Supercharger function with those disabled? Dont recall anything having affect before, and we are WELL above MAP disable 192 kPa - MAP Enable 172 kPa settings anyway with no problem until it does what it does

    Looks like injectors get cut and timing goes sky high when it happens
    Factory Stock 97 SS M6 13.51 @ 104.3 mph
    Stock Longblock LS1 w/ 233/238 P.S.I. Cam
    10.81 @ 126.9 Full interior, six speed on 275 radials, a decade ago

    '99 TA trunk mounted 76mm 6 Liter
    9.0s in '09 @ 153 MPH

    Turbo 5.3 Volvo 740 Wagon
    32psi and still winding out 5th on the highway somewhere

  5. #5
    Advanced Tuner PGA2B's Avatar
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    My bad. I saw LSA and thought S/C.
    2013 OBM A6 CTS-V Coupe
    Mods: Headers back Billy Boat Exhaust, GripTec 2.65, 8.6 PowerBond Lower, LSX Innovations Solid Isolator, ID850's, NGK TR7IX's, Accel 9070CK Wires, Spectre CAI, SRI Ported Throttle Body, SRI Catch Can, NGK AFRM, 160* T-Stat, 0fx2gv Brick, Hard Line Delete W/3/4" Lines, FB 101 FMIC, Pierberg CWA50, Stoptech Drilled/Slotted Rotors, EBC Redstuff, Cut Stock Springs, Flat Bottom Steering Wheel
    2006 Black Raven STS-V (Traded In)
    Fully Modded: 459RWHP@5888rpm/451lbft@4696rpm

  6. #6
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    Looks like you have an issue with B2 O2 sensor, its pretty much flat-lined in both logs except at the end of the first log. Are you tuning in open or closed loop? STFT arent being logged in "17" but they are in the first one.

  7. #7
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    Quote Originally Posted by ZincGT View Post
    Looks like you have an issue with B2 O2 sensor, its pretty much flat-lined in both logs except at the end of the first log. Are you tuning in open or closed loop? STFT arent being logged in "17" but they are in the first one.
    Yes you are correct. First thought it was lazy old o2, replaced it and the new one looks the same. After some pulls and some heat are put in it, starts to switch a bit more. Im thinking the car has an issue with that o2 heater circuit. After seeing them acting up I killed the closed loop because it would randomly start leaning out that bank because of it
    Factory Stock 97 SS M6 13.51 @ 104.3 mph
    Stock Longblock LS1 w/ 233/238 P.S.I. Cam
    10.81 @ 126.9 Full interior, six speed on 275 radials, a decade ago

    '99 TA trunk mounted 76mm 6 Liter
    9.0s in '09 @ 153 MPH

    Turbo 5.3 Volvo 740 Wagon
    32psi and still winding out 5th on the highway somewhere

  8. #8
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    Maybe you can post a copy of the tune and someone will spot something goofy.

  9. #9
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    Quote Originally Posted by ZincGT View Post
    Maybe you can post a copy of the tune and someone will spot something goofy.
    Thought I did...
    Attached Files Attached Files
    Factory Stock 97 SS M6 13.51 @ 104.3 mph
    Stock Longblock LS1 w/ 233/238 P.S.I. Cam
    10.81 @ 126.9 Full interior, six speed on 275 radials, a decade ago

    '99 TA trunk mounted 76mm 6 Liter
    9.0s in '09 @ 153 MPH

    Turbo 5.3 Volvo 740 Wagon
    32psi and still winding out 5th on the highway somewhere

  10. #10
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    Just looking at it briefly, this may just be personal preference but for "RPM Limit" you have it set for fuel cut, I don't like using fuel cut on anything with major modifications, I know you aren't near your rpm limit but your EOT limit does have 4500... maybe try adjusting that and disabling the wheel hop control in torque management... something to try at least.

  11. #11
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    Quote Originally Posted by ZincGT View Post
    Just looking at it briefly, this may just be personal preference but for "RPM Limit" you have it set for fuel cut, I don't like using fuel cut on anything with major modifications, I know you aren't near your rpm limit but your EOT limit does have 4500... maybe try adjusting that and disabling the wheel hop control in torque management... something to try at least.
    If you cut ign with 1400hp worth of E85 in cylinder, things can hydrolock and bend rods and other fun stuff.

    RPM limits are never changed but does it with one pound more boost then stops if you take that pound back out

    wheel hop doesnt hurt to try
    Factory Stock 97 SS M6 13.51 @ 104.3 mph
    Stock Longblock LS1 w/ 233/238 P.S.I. Cam
    10.81 @ 126.9 Full interior, six speed on 275 radials, a decade ago

    '99 TA trunk mounted 76mm 6 Liter
    9.0s in '09 @ 153 MPH

    Turbo 5.3 Volvo 740 Wagon
    32psi and still winding out 5th on the highway somewhere

  12. #12
    Tuning Addict blindsquirrel's Avatar
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    'Control Method: Spark' is confusingly named, it doesn't cut spark, it pulls timing. Unless E67 does it different than E40. Set the limiter to something stupid low and test it.

  13. #13
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    Quote Originally Posted by GrannySShifting View Post
    If you cut ign with 1400hp worth of E85 in cylinder, things can hydrolock and bend rods and other fun stuff.

    RPM limits are never changed but does it with one pound more boost then stops if you take that pound back out

    wheel hop doesnt hurt to try
    I feel like its no different then 2 step or anti-lag

  14. #14
    It looks like a hole in your VE map, MAP pressure doesn't change but your VE airflow falls overs and fuel is correspondingly pulled. What does it do if you run in MAF mode?
    2010 GXP Maloo ute, LS3, 6L80E.
    MM heads, 240/252@50 solid cam, 12.75:1 compression, 4500 Dominator converter, 3.46 rears.
    Shooting for 10s eventually.

  15. #15
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    Quote Originally Posted by Xjas View Post
    It looks like a hole in your VE map, MAP pressure doesn't change but your VE airflow falls overs and fuel is correspondingly pulled. What does it do if you run in MAF mode?
    Finally someone noticed this, (I did on dyno) but there is no hole in the VE map its 2483 at 4400 235 kPa reports 2450. At 4535 rpm and 242 kPa table is @2500 and reports 2487 but you can already see injector pulse being pulled, timing being thrown in it (base advance goes from 10 degrees to 26 instantly), even though commanded AF doesnt change. The timing comes from it seeing gms/ cyl go from 1.95 to .66 all the sudden... but why does it do it in first place?

    After looking through every log I have, it seems like EVERY pull when it saw 24x kPa it did this. tickled 239 kPa in run14log and didnt.
    Attached Files Attached Files
    Factory Stock 97 SS M6 13.51 @ 104.3 mph
    Stock Longblock LS1 w/ 233/238 P.S.I. Cam
    10.81 @ 126.9 Full interior, six speed on 275 radials, a decade ago

    '99 TA trunk mounted 76mm 6 Liter
    9.0s in '09 @ 153 MPH

    Turbo 5.3 Volvo 740 Wagon
    32psi and still winding out 5th on the highway somewhere

  16. #16
    Maybe I'm missing something as I'm not familiar with LSA engines but the tune you posted only has the virtual VE table going to 105kpa?, if you're not using the MAF how is fuel controlled above 105kpa?

    Regardless, to me it still appears to be a VE table issue, in run 15 you can see VE drop from 2488 to 2179 and then back to 2450. Since the MAF airflow and MAP remain unchanged it appears to be an error in the VE table at that point.
    Last edited by Xjas; 07-04-2019 at 06:05 AM.
    2010 GXP Maloo ute, LS3, 6L80E.
    MM heads, 240/252@50 solid cam, 12.75:1 compression, 4500 Dominator converter, 3.46 rears.
    Shooting for 10s eventually.

  17. #17
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    Quote Originally Posted by Xjas View Post
    Maybe I'm missing something as I'm not familiar with LSA engines but the tune you posted only has the virtual VE table going to 105kpa?, if you're not using the MAF how is fuel controlled above 105kpa?

    Regardless, to me it still appears to be a VE table issue, in run 15 you can see VE drop from 2488 to 2179 and then back to 2450. Since the MAF airflow and MAP remain unchanged it appears to be an error in the VE table at that point.
    Im not sure what in the world your looking at. They are virtual VE tables, there is no "limit" per se on the scalling. Screen shot what your looking at
    Factory Stock 97 SS M6 13.51 @ 104.3 mph
    Stock Longblock LS1 w/ 233/238 P.S.I. Cam
    10.81 @ 126.9 Full interior, six speed on 275 radials, a decade ago

    '99 TA trunk mounted 76mm 6 Liter
    9.0s in '09 @ 153 MPH

    Turbo 5.3 Volvo 740 Wagon
    32psi and still winding out 5th on the highway somewhere

  18. #18
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    Quote Originally Posted by ZincGT View Post
    I feel like its no different then 2 step or anti-lag
    On anti lag your TRYING to build boost, and few lbs. Lot different fuel volume at 9psi 4000rpm on 2 step then 36psi at 6800rpm full song
    Factory Stock 97 SS M6 13.51 @ 104.3 mph
    Stock Longblock LS1 w/ 233/238 P.S.I. Cam
    10.81 @ 126.9 Full interior, six speed on 275 radials, a decade ago

    '99 TA trunk mounted 76mm 6 Liter
    9.0s in '09 @ 153 MPH

    Turbo 5.3 Volvo 740 Wagon
    32psi and still winding out 5th on the highway somewhere

  19. #19
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    its a fuel cut. injector mV/Pulse width show that clearly.

    cuts fuel, cylinder airmass reduced and timing corrects.

    what happens if you unplug the MAF entirely and remove it. its disabled but still logging frequency. I would try removing it and doing a pull.

  20. #20
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    Quote Originally Posted by lukearmstrong1990 View Post
    its a fuel cut. injector mV/Pulse width show that clearly.

    cuts fuel, cylinder airmass reduced and timing corrects.

    what happens if you unplug the MAF entirely and remove it. its disabled but still logging frequency. I would try removing it and doing a pull.
    Pretty sure I logged Fuel Cut status bit on some of the pulls, and fuel cut usually cuts it all not some?
    Factory Stock 97 SS M6 13.51 @ 104.3 mph
    Stock Longblock LS1 w/ 233/238 P.S.I. Cam
    10.81 @ 126.9 Full interior, six speed on 275 radials, a decade ago

    '99 TA trunk mounted 76mm 6 Liter
    9.0s in '09 @ 153 MPH

    Turbo 5.3 Volvo 740 Wagon
    32psi and still winding out 5th on the highway somewhere