Question about knock in my datalog

[raycer]

I finally did a WOT 3rd gear data log. I'm new at reading the results.
I am seeing 26-27 degrees of timing with the knock sensor showing 3.0-3.5.
It is a Bama tune. Am I to assume that the car is being commanded around 30 degs timing and that the knock sensor is subtracting 3 degs?
I am running 94 octane . Assuming it is false knock, I looked for exhaust touching the body. I have stock manifolds with Magnaflow catback. I noticed the pipes near the rear pumpkin are very close and will bang if I hit them even lightly. Is this a possible cause of the knock or is it to far back in the exhaust to trigger it?

Thanks

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[SolarFlare]

"3" or "-3"? If positive buy and add torco or octanium and put in 8 gallons to mix. Try again and log it.

 

[raycer]

"3" or "-3"? If positive buy and add torco or octanium and put in 8 gallons to mix. Try again and log it.

+3

 

[markmurfie]

Can you post the log? what device are you using to log with? Sometimes you need to see the trend in the spark advance correlated to the knock value to figure out what the knock sensor values mean. If they switched you over to a per cylinder knock strategy, positive could be adding. It doesn't seem reasonable to command 30 to get 26-27*, more likely commanding 23-24*.

 

[raycer]

Can you post the log? what device are you using to log with? Sometimes you need to see the trend in the spark advance correlated to the knock value to figure out what the knock sensor values mean. If they switched you over to a per cylinder knock strategy, positive could be adding. It doesn't seem reasonable to command 30 to get 26-27*, more likely commanding 23-24*.

Tried to upload but it says invalid file. I am using sct4.

 

[markmurfie]

Valid file extensions: bmp doc gif jpe jpeg jpg pdf png psd txt zip

Zip the file or just change the .csv extension to .txt or any of the other ones.

I Think the admins should change it to allow .csv files.

 

[raycer]

Here it is

 

[markmurfie]

Above 5400RPMs torque source went into anti shuffle mode which cut spark a lot then it came back in trending high. Can't really tell what they are commanding for spark in anti shuffle mode with out a big assumption of what the ECU is determining. I like the way the exhaust cam is moving in the higher RPMs, but are they commanding that or is that the ECU and where your high commanded spark is coming from. You just couldn't tell with out seeing the tune file.

Below that in torque source 0 the timing curve is aggressively commanding 26-27*. Between 3500 and 4500(peak torque and efficiency) spark will usually dip to avoid knock and if it stays above 20* on 93 you're doing good. Yours doesn't get below 23* with how aggressive it is. Looks like - is adding and + is removing spark advance. You can tell from the event just after 5000 knock goes from 2 to 3.5. spark goes from 25 to 23.5.

http://datazap.me/u/markmurfe/log-1504226292?log=0&data=6-16-19-22&solo=6

 

[raycer]

Ok thanks for taking a look. So I don't need to worry about the +knock?
I did forget to turn off advance track before the pull, not sure if that makes a difference. I also hit a small bump in the road which caused a bit of slip as seen on the rpm line. I will make a few more pulls and add some octane boost and see if anything changes.

Thanks

 

[markmurfie]

This knock looks real. I would ask them to revise it some more. You should not end up with less total spark advance just a safer tune.

Maybe you got their cylinder 8 delete tune.

 

[raycer]

I went and filled up with fresh gas, 94 octane same as before and added a can of NOS octane booster. Made another log. Attached. Big difference from some octane boost. I was surprised. 30 degs plus across the board. Seems a bit aggressive tune. While I was logging, I was thinking wow this feels good. Check out the log.

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