datalog showing knock

[acrbill]

I have done a few datalogs with different tunes and they are all showing some levels of knock.

This particular log is of a SCT strategy tune but I show knock with a BBR and VMP tunes.

I am not hearing any audible knocking.

Here is a spreadsheet of my run.

anyone have any input here?

 

[92hatchlx]

How did you take that from SCT to excel? I want to plot my AFR and put in the equations for my lambda reading but don't want to hand type all of them. Assuming you didn't hand type all of that lol.

 

[afro]

I'd love to see the logs on guys running 87 octane.

What octane does the tunes suggest?

-fro

 

[jas11151990]

Im pretty sure Its not unusual to get some slight knock if I am correct, hence why we ave knock sensors to pull and adjust timing.

 

[scott_0]

youre gonna have some knock here and there, sometimes gas isnt the highest quality. the KS are pulling timing which is good as they are working, and its only pulling 1.5 degrees max and for a short time. Id have your tuner take a look at the logs as well

 

[351inside]

Damn 29° of timing, if its pulling -1 on timing I would take one degree off the total global spark, that should probably net you 0 knock...

 

[acrbill]

Damn 29° of timing, if its pulling -1 on timing I would take one degree off the total global spark, that should probably net you 0 knock...

What kind of timing advance do you think this car wants to see?


As far as the spreadsheet goes.

In livelink click on "File" in the upper left hand corner. Then "Save current datalog view" it will save it as a .CSV file which opens in Excel.

Isn't the lambda conversion (Lambda X 2)+10 for gas ?


I am going to burn off the rest of this tank of gas and put some different stuff in and see if that helps at all. I will post up my results in another thread so we can start a knowledge base so maybe we won't be so under the thumb of remote tuners.

 

[351inside]

In all honesty my tune is at 26 timing and in the lower rpms like between 4k rpms to 4500 rpms I get a neg two on the knock sensors which last les than a second after that I get no knock at all. Before that my total timing was at 28 but I wasnt comfortable with the amount of timing it was pulling... It yours seems like a good tune as is but id put it,at 27 just to be on the safe side you never know when you might get a bad batch of gas. Then if you want for the track run the 29° and a few gallons of race gas I thunk youll be ok then

 

[acrbill]

Thanks for the info.

I put up a data log thread here.
http://www.svtperformance.com/forum...5227-datalogging-think-tank.html#post11143584

 

[wbt]

Too much timing IMO. Need to get with your tuner on that. 25° on 93 would be the max. I am running high 20's on e85.

 

[CPRsm]

Do you have long tubes ? I haven't seen anything on it with these cars but stand alone companies have tried knock retards and a lot of them will tell you because the freq changes with long tubes, and amplifies noise, they don't work very well because of false knocking. Pulling the plugs and checking for detonation is more accurate than a sensor. Pull them and verify and if it is knocking, change the tune.

 

[cbrtrx]

Too much timing IMO. Need to get with your tuner on that. 25° on 93 would be the max. I am running high 20's on e85.

I have to agree, way too much timing.

 

[acrbill]

No long tubes. In fact the reason I am running the strategy tune is because I put my car back to stock and needed to adjust for my 4.10 gear.
I went -2 on the global spark and will give her a run tomorrow and see where I stand.

Do you have long tubes ? I haven't seen anything on it with these cars but stand alone companies have tried knock retards and a lot of them will tell you because the freq changes with long tubes, and amplifies noise, they don't work very well because of false knocking. Pulling the plugs and checking for detonation is more accurate than a sensor. Pull them and verify and if it is knocking, change the tune.

 

[Shaun@AED]

How are these +5 global tunes still available?

 

[scott_0]

yeah 29 degrees is too much on these cars, may get away with it in the cool air but in the summer youll be a #8 statistic. thought we all learned to stay away from global timing with these cars?

 

[PhantomX]

How did you data log it? My SCT won't pull any values except timing, just all zeros. On that note my car maxed at 25.5 degrees which is pretty much maxed. I have an o/r X so it seems good nothing audible and timing doesn't seem to drop off at that level.