Spark timing question

[joelit11]

I'm working running into an issue with my advance being too high around 2800 to 3200 rpms and I'm picking up slight knock. I've tried pulling timing in the cells that it's happening and I'm still getting way more spark than I'm asking for. The amount its using is the max on the mbt table and that's the next thing I was going to mess with but I'm still pretty green at this and it says not to mess with that so I figured I'd bounce it off some people in here and see if that's what I need to do or if I'm even looking in the right spot.

[5FDP]

What vehicle?

What fuel?

Modded or stock?

Is it real knock or burst knock?

[joelit11]

2011 camaro ss full Bolt on with a texas speed stage 3 cam. I'm pretty sure it's real knock because the retard on it starts stepping up in increments and the guy that tuned it has it running like 36? of timing which seems crazy high to me but I'm not really experienced enough to know that definitively.

[RobZL1]

Under wot or just cruising? If wot, 36 is WAAAAY too high.

[mbray01]

How about posting the tune, and we can see if anything is amiss.

[joelit11]

I'll post it when I get back to the house in an hour or so. I went ahead and tried pulling some out of the mbt table and it's still trying to run 35? or so around 3 grand under medium acceleration. The fuel trims are pretty close on the maf side and I've roughed in the sd off my long terms. This car was "professionally" tuned right before I got it but the more I've learned about this the more I realize dude did a half ass job on it.

[mbray01]

35 degrees in middle range, low load areas is not high, thats actually stock. Timing between 2800 to 3200 rpms on stock timing at medium load is between 34-40 degrees. So it goes back to is it actual knock, or false knock.

Pull a stock tune from the repository, and i bet youll see the numbers in those areas are stock/havent been touched

[joelit11]

heres my tune after i pulled a couple degrees from mbt around 2800 to 3200. it seemed to help and im only getting small blips of knock now that are probably just predictive but id still rather air on the side of caution.

[joelit11]

Also it looks like the majority of my table in the higher loads and rpms is flattened out to 26?. It doesnt knock in the upper rpms at all but I'm sure it could be better. I'm pretty comfortable with the fueling side of things but the spark honestly scares me a little just because I know how being wrong on that and making a rookie mistake might just cost me a 5 grand engine. Any advice on this would be greatly appreciated.

[5FDP]

And here I thought we were talking about a lot of knock.

Frankly you are worrying way too much about something that doesn't matter. The 1 degree or less of knock you are seeing is a non issue. I wouldn't even bat and eye at this. You will drive yourself mad if you want to remove it all. The max knock in that whole log was about 1 degree, that can not and will not harm anything. You should see a stock calibration and look at the amount of knock they have built into them even on 93 octane fuels.

[joelit11]

Thank you that makes me sleep better hearing that. what do you think about how my timing table plains out on 26? for a 1/4 of the whole table I'm sure that could use some work because I've never seen one look like that

[5FDP]

The timing at 26 degrees like that is fine. If you wanted it to hold 26 degrees at full throttle at that cylinder airmass, that is what you would do for timing.

This being a NA car won't see over 1.00 cylinder airmass so it's easier to just make everything from like .70 to 1.36 the same exact number. The area above 1.00 would be where you'd be with boost but you don't have a supercharger or turbo charger on this car.

A dyno would like you fine tune the spark timing. You could see if lower timing at lower rpms made more power, then you ramp the timing in up top. You could also see if the car stopped making power whatever value of timing. Then you'd know that say after 25 degrees it didn't help any and you could flatten it out.

[joelit11]

Yea I figured to get it perfect it would need to see a dyno, so far this is the only thing I've ran into that really gave me any trouble and didn't do what I wanted it to do but that's only because it sounds like what I was trying to do to get that last little bit of knock outta there is pretty much impossible and unnecessary even if I could pull it off. Thanks for the help man.