Trying to improve tune on new LS3 based 415 stroker

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Have a new drag and drive build 2006 GTO with a LS3 based 415 stroker that I'm struggling with the tune for. Need to at least get it good enough to go for tuning. PCM is P59 gen3 5.3 stand alone harness set up to run speed density w/ IAT sensor (no MAF), DBW. Engine is 11:1 with CNC ported heads, L92 intake w/ ID725 injectors and adapter to 78mm tb, 234/248 650/625 cam, 1 7/8 headers to 3" exhaust w/ O2's in collectors. Trans is PG with stall convertor, using ABS sensor for VSS. Using gen 3 sensors to match the PCM. Fuel system is 340lph in tank w/ 8an to Aeromotive bypass regulator set to 50lbs, 6an to fuel rail.

Have modified the base tune for the larger engine size and injectors, and revised several of the fuel & spark tables based on speed density and research on what others have done with LS3 strokers.

Here are concerns:
1. takes several tries to get to start (8 in the attached log file), and requires manipulating the throttle until it runs a while, not sure what cause is?
2. log shows lots of spark (around 40 deg) until it runs for a while, then settles down, but went back up when engine was revved up some, not sure if it's ECT adder, idle overshoot or ?
3. fuel still showing rich according to ST/LT adjustments, research says reduce the VE table, correct?
4. can't get knock sensors to show up for logging in VCM scanner, even after turning codes back on (using LS3 sensors with adapter cable to gen 3)
5. the fuel and spark tables were revised base on research and tutorials found on HPtuners, are there obvious issues that need corrected?

Also have video taken during logging if that helps.
https://youtu.be/6AD_CUHflBA?si=khWyp7HXK4vrRzoZ

[1 old guy]

I'm probably not the guy but..
Looks like that's a LOT of fuel. Long terms are at -9 to -25 short terms are in the -8 range. I only have some experience with my gen 3 408 but your VE table may need some attention

[1 old guy]

Ive attached my tune file for my 408 in SD. hopfully it will be of use

[[email protected]]

Ive attached my tune file for my 408 in SD. hopefully it will be of use

Thank you for the tune info, see some things to adjust.

Are you using knock sensors with this tune? I can't get the channel to show up in VCM scanner so that they can be logged.

[1 old guy]

I've attached a generic run I made today so you can see my layout. KNOCK is monitored on the bottom chart vs time and in the upper "SPARK RETATRD" graph.

Did the VE table help?

BTW your long and short tern fuel trims are on.

good luck with it!