sevinn

For once it wasn't total BS, but I totally agree.

realcanuk

Since iats and afr are not in the log, its hard to tell anything, but...

Your iat table pulls 3 degrees at 86. Even if its cool outside it doesn't take much of a hit to see 86 iats.
The AFR correction could be pulling a degree... a guess based on what your pe is set at.

Also who knows what the unplugged MAF can effect......

NJ_phil

I'd post the log but it's too big. ECT never got above 175f since it was 24f outside plus I was doing 70mph but it's possible IAT got above 86. Leaving that IAT table stock until I see what happens when I spray meth on it.

Initially I had burst knock during throttle stabs so I slowed down the throttle opening rate rather than see it in the logs but Shpenxel might be right and it might be back. My understanding is burst knock isn't really knock but is the ECM anticipating knock during rapid changes in airmass. Would be nice to increase the allowed airmass delta but there's no way to edit the axis in the table so I'll just zero it out and keep an eye out on real knock.

schpenxel

ECT and IAT spark changes shouldn't be going in and out as fast as the timing is changing in that screenshot, so that's why I keep harping on burst KR since it normally looks like that. Could be some sort of torque management too (or, instead of)

Either way shouldn't be bad to figure out once you're logging

Yeah, burst KR is basically what you said, removes timing during quick airflow changes to help avoid real knock

tblu92

It does not matter what the actual outside temperature is-----The IAT sensor is under the hood where the temp is very warm----Even on a cold day IAT temps can spike to 130-140* because the IAT sensor gets heat soaked and begins to read underhood temps rather than incoming intake air temps----
If your IAT gets heat soaked and spikes to 130* it takes about 15 minutes or so of driving over 30-40 MPH to get the sensor to cool down---IAT heat soak is a huge issue is tuning spark timing on any LS engine------Tuners will typically "desensitize" the IAT deduct tables so the heat soak is not an issue---
Burst knock is a whole other issue--if you delete ALL the burst knock tables your engine will ping---on a hard launch-- it is a very touchy table----best is to "limit " the burst knock rather than to delete it----
In addition to burst knock----there is:
Launch spark
Fast attack knock
Octane scalar
Knock threshold
All these tables affect what you get as "actual timing"

NJ_phil

More like 100% correct it was burst knock. I didn't think it was BR because always thought BR was protection only against rapid airflow changes but it looks like protection for anything that can cause knock. I'm guessing the extra low IATs didn't pull the usual 3* and kept the base * @ 13 so it wound up pulling timing through BR knowing the motor couldn't handle that.

Not going to mess with any knock settings for now and glad to have the protection, just dialed * down to 9 until I get WOT AFR to track better.

Thanks again man..

schpenxel

Yeah on FI applications airflow is so high pretty much everything is considered a large enough change for burst KR to do its thing

It's Always an option to turn it down later, shouldn't hurt anything though, just keep an eye on it and make sure it's not doing anything crazy like pulling 10+ degrees

tblu92

Most all tuners will totally delete the " fuel mixture spark correction table"

realcanuk

Yes, I know. I zero it myself but the op may have not.

NJ_phil

Thanks, I blew right by that in didn't know it was there. Zeroed it out.
I want spark to follow the base map until meth is pressurized and only add it then.

tblu92

If you are referring to me-- That my posts are all BS it is because the items I mention are all over your head---There are about 200-300 posters on this forum and most likely maybe only 4 or 5 full time tuners--Me being one of them----Don't criticize something that you have no experience at----I doubt that you have tuned over 1500+ GM cars and trks-----I use only facts that were taught in EFILIVE tuning training---so if you dis-agree you are entitled to your opinion---But that's all it is an un informed opinion---

sevinn

Yeah, all over my head I don't know a thing.

We've been through this before, I'll save my typing this time and finally add someone other than cow to my ignore list.