C6 ls3 VVE issues. Getting knock at low rpms

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Hi,

Newbie here. I have 2009 C6 with few bolt ons( CAI, Long tube headers, catted xpipe, Fast 102, ported throttle body, bbe exhaust).
I was able to get MAF tuned pretty close but having issue with VVE tuning. I am getting knock upto 4 deg even at low rpms. Following the guide from tuning school. Posted question for them but at the same time trying to get help from forum friends here.

Any help will be appreciated.

[GHuggins]

Haven't looked at the logs or tunes yet - just a fyi in regards to that - sometimes less is more You can post 1 log and latest tune then list the problems and build. Seems to make responses go quicker.

Anyway - what kind of gas are you running? Are you sure you don't have anything rattling? I've seen suspension bottom out cause a couple of degrees to get pulled.

You can de-tune your knock sensors so they aren't so sensitive - Actually common practice, so you don't have to worry about it. Just increase them 25% for starters and make initial something like 180 to 200. This is if it's not actually knocking.

[GHuggins]

Just checked the tune and the last log. Your air models are looking good. Some of the higher rpm stuff is off especially in decel areas, but for the most part it's really really close to being spot on. As for your timing models, you might want to smooth things some more.

I assume you don't have it going into PE that quickly for fuel economy or fuel tuning - your using a wideband for that, so unlikely on that one...

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Thank you for the quick reply. I did check for rattling. That was my suspicion too. But ruled out rattling. Did try to desensitize the knock sensors by changing the multipliers but didnt touch the Initial level. May be I will bump it to 180. My concern is when I am shifting from 2nd onwards, I am seeing knock while fine tuning ve table, even at the 1600 rpm, Accel Pedal 29.3% and Throttle at 30.5%. And its been consistent. Because of consistency also i am taking rattling out of equation.
Right now for VE table tuning delaying PE, I do want PE to come early but will play with it after VE table is dialed in.
Other issue I am seeing is, as I log the VE Error, paste back in VVE table, calculate coefficients I see completely opposite results. e.g. some cells that were showing +9% error now show -9%. Trying to understand behavior of calculating coefficients and why it messes some cells completely.
But at this time I am really concerned about the knock and trying to see whether I should remove some timing.

Also can you shade some light on the smoothening of timing model please? Thats going to be my next target. Thank you once again for the replies and help.

[GHuggins]

With the VE model being that close, I would hand edit the big areas that are out, smooth to corresponding zones and then calculate. It shouldn't change it that much if you do it that way. You were basically out 1 to 2 percent in the last log you posted - I wouldn't even touch those areas. Then there were the 21 percent areas - those I would alter, blend and rework...

As for the timing - if it's consistent and doesn't go away with the knock sensor settings change, then yes - pull timing and then smooth the table out. Sometimes just having smooth transitions can fix a lot of knock problems.

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Thank you once again. I will definitely try changing sensor settings and see if knock goes away if not will try to pull some timing and smooth out the table. Also I will try manually editing some of the cells that are way off and capture the log.
I will post the log once weather gets better and take car out for a spin.