WOT run 1-2 drop-off 2017 5.7 A8

[themikecooper]

Oh wise one's I found a consistent drop off in my 1/4 mile runs have attempted to clean up but haven't found the correct table. Attached are 3 log screenshots from 2 different 12.95 runs and a 12.89 run. The shift between 1-2 is my problem any assistance would be appreciated I know its got to be something I'm over looking.

-Dogg

[rays04gtx]

I think the logs would also be helpful,

I'm going to stab in the dark here, but Table 14520 and 14521 (bobble TA) I always max those out

[DodgeBoy_8HP]

Any upgrade on transmission? Which one are you currently running? Stock tuning?

Without a specific transmission log it will be a little difficult to point the problem. However, I believe it would be:
- Shift Pressure
- Line Pressure
- Shift Timing
- Shift Schedule
- Torque Limitation
- ...

In case you are looking for a custom and personalized transmission tuning, I do offer support.

Email: [email protected]

[themikecooper]

Stock transmission no upgrades there except 3.09 LSD not really trans but could have some effect.

Logs added I didn't have the best PIDS at the time so didn't know if they would help.

-Dogg

Sorry forgot to list current transmission: ZF8HP70

[Hemituna]

Its tagging the rpm limit on 1-2 shift.
Lower the commanded 1-2 shift point a little and it will clean up.

[themikecooper]

Thanks for the quick response! Do you mean on the trans side shift scheduling? I think its set to 1310 at WOT which should shift at 6170 however I do notice its almost hitting 7000 for that shift? Or am I reading it wrong?

-Dogg

[Hemituna]

Yes it is hitting 7k for that shift.
Trans shift schedule number is maybe a little high....lower it and see if it helps.
Maybe re-enable external trans tq spark reduction also....looks like you have very little left in the way of tq reduction which doesnt help.

[themikecooper]

I will lower it from my logs its schedule 7 for sports mode. I do not understand if its commanded to 6170 why it's hitting 7k but its doing it consistently so ill reduce and test. What effect if any would the Bobble TqMgt have on this as Tip-In\Out are disabled. I have read mixed opinions however I see no harm in maxing out if needed. I also do not understand why the rest of the shifts which are set a bit higher than the 6170 have no issue shifting in mid 6k. Thanks again time to test...

-Dogg

[PurpleRam]

My reasoning for eliminating the bobble Tq is, it’s another “modifier” the ecu looks for when preforming calculations. If it sees that the Tq request is below this min it will override the disabled function

[themikecooper]

That does make sense I just made them 7200 & 160 should never trigger. Thanks for the background.

-Dogg

[themikecooper]

Looks like the adjustment cleaned up my issue from what I can tell in the logs won't know for sure till better weather is back upon Michigan and I can hit the track as we all know it's impossible to test a 1-2 shift in November on street tires (no prep) in 30 degree weather. Thanks for everyone's input!

-Dogg

[james1595]

Looks like the adjustment cleaned up my issue from what I can tell in the logs won't know for sure till better weather is back upon Michigan and I can hit the track as we all know it's impossible to test a 1-2 shift in November on street tires (no prep) in 30 degree weather. Thanks for everyone's input!

-Dogg

Ive beem having the same issue as well, i had my shift at 5600 and it wouldnt shift till almost 6700 rpm. You are saying that the bauble torque worked as far as you can tell?

[themikecooper]

I did both the bobble max out and dropped Schedule 7 1-2 upshift -70 at WOT.

-Dogg