Fartpipe

I have a 2006 C6Z06 with heads cam, intake, exhaust.
Only when I have very good traction and shift from 1st to 2nd, 2nd to 3rz and 3rd to 4th the car loses 12-16degs of timing for a random amount of time then suddenly snaps back to full timing and feels like a 100shot of hp kicking in.
If I have street tires on the car spins and literally doesn't take a single degree of timing out.
I've logged the car it shows no knock retard, coolant temp is typically in between 180-190degs, its only after a shift. Never happens in 1st gear.
Traction control turned off, complete traction control turned off.
The throttle position is not commanded shut when this happens and stays and a constant 88.0% wot during issue. Not flat shifting the car but the faster the shift the worse it is. It'll do it for a duration of 100rpm or a duration of 800rpm before it kicks in.

Thoughts on the issue and things to try.

Car already has a replacement PCM and did it with both.

atljar

I assume theres torque management still in the PCM tune someplace or wheel hop/abuse management still active. Both should be able to be disabled

Michael_D

Is burst knock enabled and/or at stock settings?

Fartpipe

It doesn't register any burst knock either during the issue.


I'll look closer at torque management.

Anyone know how I could tell if it is torque management? Or traction control or whatever?

Michael_D

It's actually burst knock retard. You have to log that PID to see it, along with knock retard.

Are you logging spark state?

I have my scanner set up to see the four relevant spark PID's in a single channel group. Spark total, KR, Burst KR, and Spark State.

Fartpipe

Ok so if it's "burst knock" how do I get rid of it or is there an issue with the car?

nuke61

It sounds like Torque Management to me. In HPTuners:

Engine --> Torque Management

If it's stock/near stock it will show ~3000 lb-ft for Trans Input Max and all the Gear number will be 3 digits, as in 103/111/155/etc. All of those are at 6042 in my H/C/I/E C6Z - this was done by tuner NicD, and similar numbers were put in on my supercharged C5Z by Ryne Cunningham. So, apparently standard stuff by tuners for higher horsepower cars.

Frans96ss

Do you have spark smoothing on?

Fartpipe

Thanks for chiming in Fran, I'll double check that when I get home but I'm pretty sure it is turned on.

Frans96ss

Try turning that off.

Michael_D

I do not disable it, but I do lower it from 12 deg max down to 4 deg max. I think it is an important safety net. It is an intuitive function that will pull spark, before the sensors detect it, based on what it learns over time.

This table...........

Frans96ss

Burst knock can be zerod... that wont hurt anything.

Michael_D

I know a lot of tuners zero it out. I prefer to keep it as I stated earlier, 4 max. It works well with the other spark table tweaks I do. Thanks for the input.

Dan_the_C5_Man

The fascination with disabling every single protection mechanism never ceases to amaze me. Unlike controls related to emissions or safety, the gain to risk benefit is just not there..

Frans96ss

Burst knock is not regular knock... so its not disabling a "safety" feature.... knock sensors etc are still fully enabled etc.

Dan_the_C5_Man

I understand the difference (to a degree), but for my edification (and others), why did GM go through the trouble to build that feature (assuming you don't like the word protection)?

Frans96ss

factory tunes are WAYYYY diff than something that a shop like mine would do. No idea why they do it. They will have 15 degree in the timing table,, take out 4 with another table then add 3 more in in another table, then add 2 more in in another..... C6 stuff isnt nearly as bad at the c7 stuff. They have TONS of diff timing tables doing all kinds of things.

RamAir972003

Most likely torque management, as far as the the throttle will always be 88% to my knowledge I thought the same thing till I did some homework but yea your putting a load on the car when it hooks so the tq management kicks in some people totally disable it but that's up to your tuner......

Depending on the level of the build, you may have to simply because the std rate of climb is so fast, it always anticipates the amount of airflow as a burst condition. This will cause erratic timing throughout a dyno pull.

Being that timing is lowered from stock with an FI build, it is generally not a problem to remove it, just properly log the car to make sure you are not having knock issue's during fast throttle changes.

Good luck with it. From east coast sc

nuke61

Any updates on what you've found?

Fartpipe

UPDATE!

It is officially TORQUE MANAGEMENT taking out the timing.

It shows up under "TORQUE MANAGEMENT ADVANCE" it'll remove 12-16degrees of timing after each shift and wont return till top of that gear and happen again in the next.

From everything I can see i have the torque limits to 6042 and nothing that shows in the tune that torque management is even able to come into play.

It leaves me with.... WHAT enables torque management? What parameters is it using to determine taking away timing? Is there something like speed sensors, remove a fuse anything so it cant access a parameter to take it away?????