Experiencing knock on acceleration (BootMod3). Help analyzing graph.

[LoveSupra]

I managed to datalog for the first time today. Stage 1 91 Octane. The knock peaks at 0.4 in this sample, and there seems to be consistent knock when accelerating as per the graph. Is this normal or significant?

The 2 indicators in the graph are Acceleration (Pedal%) and Knock Detected [0-n].

I calculated a total of 2.2 knocks over a period of 5 minutes in the graph.

I was also driving on 2 bars on the fuel gauge, so quite low on gas.

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[GMsuperfan]

Not sure about supra but in the GTI world, anything indicated on the COBB AP less than 3 for knock is nothing to worry about....if your scale on the right is Knock, all values are less than 1, which is nominal. On my Sneekytuned GTI, i've seen knock above 3 before (not consistently), it pulls 27-29 PSI on 93 octane and nothing has blown up yet.

 

[LoveSupra]

Not sure about supra but in the GTI world, anything indicated on the COBB AP less than 3 for knock is nothing to worry about....if your scale on the right is Knock, all values are less than 1, which is nominal. On my Sneekytuned GTI, i've seen knock above 3 before (not consistently), it pulls 27-29 PSI on 93 octane and nothing has blown up yet.

Yup! Can confirm the scale on the right is for knock. And yes, all values are less than 1, even on a WOT pull im not seeing anything close to 1 knock. Seen some posts about tuned BMWs pulling 14 knocks on some WOT pulls ?

Thanks for your input, I do appreciate it ?

 

[dzeleski]

Here’s some resources for you if you want to understand a bit more about knock detection and sensors.




https://tunertools.com/pages/knock-detection

These sensors are typically just microphones that filter out a bunch of noise and try to listen for engine knock. The filtering isn’t perfect. Single digit knock counts are not a problem during a pull. If you start to see double digit counts during a pull then you are going to want to look into it.

Driving around normally can also cause some higher knock counts just due to pot holes, suspension noise, road noise, etc.

 

[Zhupra_]

I managed to datalog for the first time today. Stage 1 91 Octane. The knock peaks at 0.4 in this sample, and there seems to be consistent knock when accelerating as per the graph. Is this normal or significant?

The 2 indicators in the graph are Acceleration (Pedal%) and Knock Detected [0-n].

I calculated a total of 2.2 knocks over a period of 5 minutes in the graph.

I was also driving on 2 bars on the fuel gauge, so quite low on gas.

sorry for reviving a dead chat but did you ever find the solution to this? mine is doing exactly the same

 

[zrk]

sorry for reviving a dead chat but did you ever find the solution to this? mine is doing exactly the same

Use better fuel.

 

[Jesse DaBears]

Use better fuel.

Use better fuel.

 

[razorlab]

AFAIK as I have seen so far, in BM3, the knock logging item is a either 0 or 1. 1 is knock detected. You should really be logging Ignition Timing Correction...

 

[LoveSupra]

I think it was just my burble settings affecting the amount of knock. I reverted to stock map and had slightly less knock but it was not a noticeable change.

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