Page 1 of 2 12 LastLast
Results 1 to 20 of 25

Thread: Pulling 10+ degrees of timing (torque management) before 1-2 Shift

  1. 10-15-2017 #1
    dave01gt
    dave01gt is offline
    Tuner in Training
    Join Date
    May 2016
    Posts
    20

    Pulling 10+ degrees of timing (torque management) before 1-2 Shift

    My car will always pull 10* or so in first gear before the 1-2 shift and has with several different tunes flashed over the past year. Torque management kicks in, and the car just slows down, then finally reaches the shift, pulls more timing for the shift, then picks back up. It also does it before/after in other gears, but not nearly as bad. Attached is a log. On this log I commanded 1-2 shift at 22mph and 5600 to try and avoid the timing pull, but still does. Could it be something in shift inertia, driver demand, virtual torque/Coefficients, etc? Any help is greatly appreciated!
    Attached Files Attached Files
    Last edited by dave01gt; 10-21-2017 at 12:04 PM.
    Reply With Quote Reply With Quote
  2. 10-16-2017 #2
    SSDION
    SSDION is offline
    Tuner in Training
    Join Date
    May 2006
    Posts
    35
    I have similar problem with my c7 z06 A8. My car has less power than yours and 1-2 and 2-3 shifts are some times bad. So far I have try many things and some time it work but some time it don't. I am interested to share information to improve my tune also. What did you modify on that car to get over 925 HP. How fast are you going on 1/4 mile? Post your tune so I can compare with what I have done.
    Last edited by SSDION; 10-16-2017 at 07:28 AM.
    Reply With Quote Reply With Quote
  3. 10-16-2017 #3
    dave01gt
    dave01gt is offline
    Tuner in Training
    Join Date
    May 2016
    Posts
    20
    It's a forged/Cam 416, YSI at 18lbs, LT4 Fuel System, Secondary Low Side, Circle D Pro Converter, Custom stock diff, etc. This is on Fuse Ignitor116 Unleaded. This pass was a 9.36@149. I'm thinking it should be a 9.0@153 or so once I can get the timing/shifts lined out and actually hook.
    Reply With Quote Reply With Quote
  4. 10-16-2017 #4
    veee8
    veee8 is offline
    Advanced Tuner veee8's Avatar
    Join Date
    Apr 2006
    Location
    Raleigh, NC
    Posts
    449
    From the log it looks like it spun pretty bad around 5700 rpm in first gear.
    Shifting is done off mph with the rpm as the target. If it spins it brings that start of the shift sooner.
    The torque management type, changes from "driver" to "Trans S" during that event and all the shifts. Looks like it spins, mph shoots up, the modules start the shift process, it grabs, mph goes back down, then starts the shift again.
    www.crawford-racing.com
    Home of the original and best selling CR-Fueler plug and play port injection controller kits for all GM Gen V direct injection platforms.
    Reply With Quote Reply With Quote
  5. 10-17-2017 #5
    SSDION
    SSDION is offline
    Tuner in Training
    Join Date
    May 2006
    Posts
    35
    This is very very good. What is this monster power machine? As I see your log, there is an event happening around time 1. 17 sec. car is not accelerating for a while. 1-2 Shift is happening later at 1.17.501. shift is fast 0.125 sec but car is not accelerating for a while. There is some spin of driven wheels at 1.17.058 sec. I sugest you log also undriven wheels to see mph difference. If THERE IS TOO MUCH DIFFERENCE WITH VSS OF DRIVEN AND UNDRIVEN WHEELS THE TCM THINK THERE IS A PROBLEM AND DELAY THE SHIFT. Calibration is not easy to do correctly so both speed match with real gps speed. The shift 2-3 take 1.375 sec. but car accelerate good. I see also you have a lot of TCC slip. This do not help and reduce acceleration. When do you lock TCC?
    Reply With Quote Reply With Quote
  6. 10-17-2017 #6
    dave01gt
    dave01gt is offline
    Tuner in Training
    Join Date
    May 2016
    Posts
    20
    The converter is set to lock all the time, but does not lock until 119mph. Is there a way to actually get it to lock sooner?
    Reply With Quote Reply With Quote
  7. 10-17-2017 #7
    dave01gt
    dave01gt is offline
    Tuner in Training
    Join Date
    May 2016
    Posts
    20
    I added another log where I don't believe it spins at all and still does it.
    Reply With Quote Reply With Quote
  8. 10-17-2017 #8
    SSDION
    SSDION is offline
    Tuner in Training
    Join Date
    May 2006
    Posts
    35
    SECOND LOG 9.34 is better and less TCC slip SPECIALY IN FIRST GEAR. May be because transmission oil is colder. Have you try to raise BASE SHIFT PRESSURE TCC ON table to reduce slippage of TCC? 2-3 SHIFT IS MUCH FASTER. this is a very good race but It can be improoved a bit
    Reply With Quote Reply With Quote
  9. 10-17-2017 #9
    SSDION
    SSDION is offline
    Tuner in Training
    Join Date
    May 2006
    Posts
    35
    apply/release speed table control TCC
    Last edited by SSDION; 10-17-2017 at 08:56 PM.
    Reply With Quote Reply With Quote
  10. 10-19-2017 #10
    dave01gt
    dave01gt is offline
    Tuner in Training
    Join Date
    May 2016
    Posts
    20
    I looked again and it is set to lockup in all gears at Full Throttle. Am I missing something? Any other ideas about the timing being pulled? I believe Traction Control is basically tune out in the tune and by turning everything off in the car.
    Reply With Quote Reply With Quote
  11. 10-19-2017 #11
    SSDION
    SSDION is offline
    Tuner in Training
    Join Date
    May 2006
    Posts
    35
    Every table are inter-connected together and if you change some values in a table, computer calculates and can react and close throttle, reduce power by decreasing timing or delay transmission shift. Basic torque management system was design by GM engineers in order to have better performance on road racing. The system was also design to protect all components to avoid abuse and repair on WARANTY. It is not easy to analyse your combination of modifications without having your tune. If you send me a private message with your tune, I will look your tune and give you some comments. Your setup is already very-very good.
    Reply With Quote Reply With Quote
  12. 10-21-2017 #12
    dave01gt
    dave01gt is offline
    Tuner in Training
    Join Date
    May 2016
    Posts
    20
    Tune is added. Thanks!
    Reply With Quote Reply With Quote
  13. 10-22-2017 #13
    SSDION
    SSDION is offline
    Tuner in Training
    Join Date
    May 2006
    Posts
    35
    I can't open it. What version of HPT? What is your car?
    Reply With Quote Reply With Quote
  14. 10-23-2017 #14
    dave01gt
    dave01gt is offline
    Tuner in Training
    Join Date
    May 2016
    Posts
    20
    I believe it's the new Beta. My car is a 15 Corvette base.
    Reply With Quote Reply With Quote
  15. 10-23-2017 #15
    Charlie540i
    Charlie540i is offline
    Tuner in Training
    Join Date
    Jan 2012
    Location
    Carolina, PR
    Posts
    43
    What combo of pulleys are you using for 18psi? We have a similar setup with stock cubes, but I'm only seeing 15-16psi.
    Reply With Quote Reply With Quote
  16. 10-23-2017 #16
    dave01gt
    dave01gt is offline
    Tuner in Training
    Join Date
    May 2016
    Posts
    20
    The upper is a 2.75 A&A and the lower I believe was 8.35 on a 10rib setup.
    Reply With Quote Reply With Quote
  17. 10-23-2017 #17
    Charlie540i
    Charlie540i is offline
    Tuner in Training
    Join Date
    Jan 2012
    Location
    Carolina, PR
    Posts
    43
    Quote Originally Posted by dave01gt View Post
    The upper is a 2.75 A&A and the lower I believe was 8.35 on a 10rib setup.
    We have a 2.95 with the 8.35 lower on a 10 rib setup. Are you using the latest race tensioner or the regular newer style billet tensioner?
    Reply With Quote Reply With Quote
  18. 10-23-2017 #18
    veee8
    veee8 is offline
    Advanced Tuner veee8's Avatar
    Join Date
    Apr 2006
    Location
    Raleigh, NC
    Posts
    449
    May want to make your brake torque multiplier all 1's as alcohol content goes up, not just the 0% row, also as an experiment, try not brake torquing the car up at the line, and launch just off idle. It really delays the throttle opening, and I think it may be causing the delay with locking the converter up at wot.
    www.crawford-racing.com
    Home of the original and best selling CR-Fueler plug and play port injection controller kits for all GM Gen V direct injection platforms.
    Reply With Quote Reply With Quote
  19. 10-23-2017 #19
    dave01gt
    dave01gt is offline
    Tuner in Training
    Join Date
    May 2016
    Posts
    20
    I think I've bought 2-3 different brackets/tensioners from A&A. Honestly don't remember which is on it now lol. It has the spring loaded and the manual tensioners.
    Reply With Quote Reply With Quote
  20. 10-25-2017 #20
    RickClarke23
    RickClarke23 is offline
    Tuner
    Join Date
    Nov 2008
    Posts
    165
    PM sent dave.
    Reply With Quote Reply With Quote
« Previous Thread | Next Thread »