I've been working on timing a bit. I've taken timing out here and there to get rid of knock. Burst knock seemed to be my biggest issue originally, now it seems like real knock. I've skipped around the high octane table and taken timing out a couple times now. The truck is running very good overall, but I'm afraid fo knock.
Can anybody offer some suggestions?
Knock out of heavy throttle isn't an issue really. I wouldn't even care if you saw upwards of 1-4 degrees of knock just cruising around. The highest that log showed was like 1-2 and you weren't even into the gas much. You should take a look at a stock GEN 4 5.3 truck scan, they show knock all over the place on stock calibrations.
Knock under heavy loads is much more of an issue for sure.
2016 Silverado CCSB 5.3/6L80e, not as slow but still heavy.
If you don't post your tune and logs when you have questions you aren't helping yourself.
There's nothing in that log that would really worry me. I have an L92 truck and if I pull enough timing out of it to never show knock it's just about dangerous to drive it's so slow. 200K miles on it and it's doing just fine. Still shows some knock every now and then but no issues.
Knock on a 600+rwhp car @ WOT is a whole different ballgame than some slight knock on a stock or close to stock car/truck under light throttle.
Post a log and tune if you want help
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The log is from my trip to the sandwich shop. TPS stayed under 50% or so. I'm operating under the assumption that any real knock is bad. Looking at the graph using wideband (MAP versus engine speed), the fueling error is relatively small, but using the STFT, it is larger. Is this enough to cause knock?
Happy Veterans Day
Thanks for the feedback above. My engine is only 9.5 compression. I'm hoping to put a turbo on it later... Anyway, based on the feedback above, I took a stock 2014 7.0 liter Camaro High Octane timing chart and multiplied the whole chart by 1.05. While doing a VVE experiment today, I also logged the knock retard. I can't upload the whole scan because it is too big, but here's the graph. I never got into PE and the TPS never went higher than 42% (spent most of the time in 20-30 range) or so. The goal was to roll into and out of the throttle at a slow to medium pace.
Knock Retard 11.11.JPG
I have more KR hits and the numbers are larger than yesterday. Most of the hits (and biggest hits) are in 2000 -3400 range At what point do you call knock too much knock? What's the best method for adjusting timing? Would you increase timing a bit more - and would you do it anywhere in the range specifically? It almost looks like I might get more power by adding timing above 4,000 rpm.
Thanks in advance. No pun intended.
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Go to areas where knock starts and pull a degree out of that cell. Alot of times a degree will escalate to more in the sequential cells after even when there is nothing actually knocking there . You will notice this when knock starts and goes into following cells and increases or holds same is true if it knocks and you release accelerator and it runs up the map too
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