I have a 2012 L96 6.0. I had it bored out 0.030". I installed flat top pistons with valve reliefs. Im running a stock head gasket with stock GM 823 heads. I installed a Texas speed LS L92 truck cam. Specs 220/232 0.600 lift 112LSA. Long tube headers and 3 inch exhaust. I had it tuned by Blackbear.
The truck often dies when flirting with the throttle like when backing into a spot or slow moving in traffic. It also bucks at low rpm lugging. At full throttle it struggles and feels like it should run better. I have contacted blackbear multiple times with data l logs and they said every thing is normal. I have replaced wires, coils and plugs. I have replaced mass air, o2 sensors, manifold pressure sensor, cam position sensor and the crabk position sensor. I'm no tuner but would love to learn. I hooked up my EFI live today and watched the spark advance. Im running 92 octane.
I took a video with my phone of the v3 screen.
In park idle 730 rpm jumps from 16-21 Spark advance.
1100 rpms 47 spark advance
1500 rpms 47.5 spark advance
3118 47.5
In drive holding brake
1039 rpm 44.5
1256 rpm 45.6
​1480 rpm 44
1672 rpm 42.5
1962 rpm 41.5
2038 rpm 41.5
Air fuel ratio 14-1
Seems Spark advance may be to blame.

 

How so? Looks pretty normal to me.

Your symptoms sound more like a vacuum leak affecting idle and/or injectors need cleaned affecting WOT etc. Maybe even a fuel pressure problem.

 

47 degrees BTDC isn't to much?

 

No. Sounds fine to me. In old mechanical distributors, we'd shoot for about 36° or so at full power, and about 10 - 12° more cruising; so what you have sounds pretty much ... normal. What one should expect even.

What makes you think it's a problem?

 

Well the bucking at low rpm lugging makes me think its ignition related. I pull a 7000 lb camper and I can feel it bucking at wot. I have cutouts on it and I can hear the stumble in the exhaust when its bucking with the cutouts open. I did a little more data logging and found it runs at 14.11-1 AFR pretty much all the time except at WOT it runs at 11.9-1 AFR. Is this normal?

 

Have you discussed it with Black Bear? Have you sent him any logs since?

 

Yes I sent multiple data logs back to blackbear and he said all looked normal but more power could be made. Not sure what that means.

 

Also when it bucks the KR is 0 I have never seen the KR change from 0° could the knock sensors be the problem?

 

47* at lighter engine loads is fine.

Can you email your tune and datalogs?