Made a few logs at the track and noticed a spark issue that i may need some help with. First the stall is a 3600-3800 circle D. Stalling about 1500rpm staged up timing is ~40* then when taking off the spark goes down to 14.5* then back up to 26.5* at around 4100rpm and remains wt commanded for the rest of the run. I commanded the specified cells in my spark table to 35* and now get somewhere around 21*. Don't know why its dropping for this short amount of time but i need to correct it. Any ideas of wt can be checked?

 

post up your log... and tune....

 

Log "Burst knock" see how much it is pulling...

 

More than likely that is your answer. Also, confirm you are using the HI octane timing table...

 

I copied the high oct spark table to the low oct table so it should be commanded.

 

also make sure your TQ management is disabled because it will pull timing also..

 

Mine does the exact same thing. It is actually a good thing for me as it spins a lot. It is my built-in traction control, lol. Someone here asked about pulling timing for launch control well here it is.

Attached are some logs of some runs I made at the track.

The first one I was peddling it because I lost traction off the line. You can see that every time I stab the peddle the spark goes way down sometimes negative. It is almost a mirror opposite of the throttle.

The second and third runs you can see I tried launching at 50% throttle to get traction.

I also need to get a IAT relocation adapter because my IAT's are always really high do to heat soak and that pulls timing also.

 

My truck was pulling timing at launch and the only way we were able to stop this was to disable all Torque Management.

A customer at a friends shop, 08 Silverado Ex Cab 4x4, built 5.7L w/turbo. They had a problem with it pulling timing, turned out to be a knock sensor.

 

No, there are many other tables that factor into timing. The high and low tables are just kind of a "base" table, (actually base idle is), Anyways, point is, you have multiple tables the affect actual timing no matter what you put in the hi/low tables. Torque management is another good place to check, but from what you are describing, I'd be sure and log "burst knock" aswell...
Feel free to post up a tune file

 

This sounds very much like Burst Knock and an easy problem to fix. It can be tuned out though so I would highly suggest that you dont just go and zero out the burst knock table because that is kind of a lazy "half ***" way of taking care of it IMO and because burst knock does serve it's purpose in the tune.