Stockish L86 part throttle pulling timing normal?

[Slow6.2]

Hello all!
So Ive noticed that my truck seems to have a whole whack of KR at part throttle under load (like going uphill with tcc locked) and is almost pulling 10 degrees under WOT. Ive thought that maybe it was engine noise from headers so I had desensitized the sensors 10% but then I heard audible knock at WOT so I put back to stock. Ive uploaded a scan of mixed driving, and sure enough it pulls a fair amount in normal driving. Ive searched the forum but havent found much like my situation. The tune is basically stock on the timing and fueling, only a few modifications to the transmission, cat delete, and the deletion of DOD. I havent calibrated the MAF yet due to no WB, the LTFTs are negative so maybe its pulling too much fuel? Shitty winter gas?
Truck has:
6.2 L86 6L80
AFe "cold air" intake
Pacesetter 1 7/8 longtube headers 3" collectors into 3" Y pipe, 3" 50 series muffler and 4" tailpipe
Half assed ported TB, basically smoothed the lower sharp lip.

Thanks in advance,
22-03-21 16-16-21.hplSILVRADO SPARK TEST TUNE dd stock.hpt

[lucas287]

87 or 91/93 octane fuel?

[lucas287]

I will say the factory spark tables are pretty aggressive. It's rumored that they weren't actually created on pump gas.

[5FDP]

If the headers are touching anything, the sensors are likely to pick that up too. Make sure nothing is rubbing.

[Dominatorstang]

Take what I say with a grain of salt, but maybe it will help some.
I am pretty sure our L86's require premium octane stock, but yes I would agree that looks much worse than just low octane fuel. I have heard some cold air systems throw the MAF pretty far off, but your MAF curve looks way crazy to me. What elevation are you? Your MAP is getting down to 89kpa at WOT with an aftermarket CAI, could also be concerning.
Not sure how much this helps but worth a try... try logging any PID for knock retard, meaning burst knock retard, each cylinder knock retard and anything else with the label. Maybe it will help narrow down some.

[GHuggins]

It may just be junk gas. I've been seeing this a ton here lately with gas prices soaring. The others above are also correct, especially about the cai throwing off the maf, but did this just recently start? Especially if your in California or the central south US regions running 91 - I've tuned some vehicles these areas lately that are head/cam only real mods and are running less timing than some boosted setups I've done. Just tuned a 5.3 in a silverado today that was running cheap gas and had to pull about 5 to 7 degrees out of my normal 5.3 tune, but it was also a stock manual trans and would lug the engine more - first one of those I've seen... Really sucks that gas is this junky and also so damn expensive.

[Slow6.2]

Thanks for the replies everyone! Im up in Edmonton Alberta so about 2100 ft or so elevation and around 100kpa baro most days. I run nothing but 91 in it, have tried running 93 occasionally but didnt make enough of a difference to continue (especially with the prices right now). I think I will just have to bite the bullet, install a wideband and make sure my MAP and MAF are correct and go from there. If it still does it afterwards, maybe the factory base map is too aggressive for the shitty pump gas here and Ill pull some timing in the troublesome areas. Ill report my findings after I square up the sensors. Im still quite novice at tuning so I appreciate all your help!

[lucas287]

You don't need a wideband to dial in your MAF. Actually, I think most recommend using the stock narrowband o2's for part-throttle and then a wideband for WOT.

[Slow6.2]

Thanks man, I looked into it and found out how to log LTFTs for VVE and MAF. Built some histograms and Im gonna go out here and log this evening. I have a couple tunes with the MAP and MAF disabled (not both at once, mind you) so hopefully all goes well and I get some good data.

[Slow6.2]

So yeah, turns out its shitty fuel. After calibrating the MAF and logging VVE (LTFTs were -2 or so so I didnt mess with the table) I threw half a tank of 102 on top of the 91 in there and the KR went away 100%. I guess Im gonna be pulling some timing here once this tanks done. Thanks for everything guys, much appreciated!