Turbo car - pulling more timing then commanded. Anyone seen this before?

[LS1Nova]

Ok, both me an the tuner are stumped here. We are commanding 17* timing and sometimes ending up with 7! As an example @ 5400 and 210kpa my base timing is 27* and subracting 10* at that kpa so I should end up with 17 right? I'm getting 7*. No knock, ECT is not pulling timing, IAT's are not pulling timing. Don't know what's going on with it. We tried turning off the knock sensors, zeroing the iat and ect tables and nothing changes it.

Here's a run down of the engine
402ci ls1
twin turbo
cos3 3bar
engine is in a 64 Chevy II

any Idea's?

[ChipsByAl]

It might not help but I would recommend to log DynCylAir_DMA to accurately show where you are in the spark map.
Al

[LS1Nova]

I did in some other logs and it was in the far right 1.20 cells

[LS1Nova]

I'm also baffled as to why the timing is bouncing around so much. It's jumping up and down 3 and 4 degree's throughout the pull.

Check out this log

[ChipsByAl]

Maybe log the rest of the DMA and Burst Knock spark retard PIDs (. Make sure you log GM.DYNCYLAIR and not GM.CYLAIR

[LS1Nova]

hmm, should the burst knock be disabled for a fast spooling turbo car?

[joecar]

Log the EST_xxx_DMA pids first (before disabling BKR) as Al said.

[joecar]

Frank, can you post your .tun file also, if that's ok...?

:)

[LS1Nova]

Thanks for the great advise guys! I'm going to try to get out and log all those pids tonight. Hopefully that will reveal what is going on. Joecar, I added the tune file to the original post.

[LS1Nova]

Thanks for the help everybody! I finally got it today. Logged some of the dma's and found out it was Burst knock. Pulled 6.8*. Zeroed it out and logged another file and now the timing is solid as a rock and right where it should be.
Thanks for the help!
Frank