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Hello, it is logical to listen knock at 15 degree at 4500 rpm on an engine with turbo 0.6 bar boost and 9.5 compensations? Or something is wrong ?
We need the full story. What is the engine, transmission ,vehicle? Is this a new knocking sound or did it always knock there? When you say "knock," are you hearing it with your ears or is your ECU telling you it's knocking? What ECU is it? What modifications does the engine have?
You are right, it is a bmw m42b18 turbo, new engine build with 9.5 compensation. Link ecu storm ,I have had many problem with trigger and I solve it. I use knock monitor plex. And I listen knock at 0.6 bar boost with 15 degree. I believe that I can have more ignition
there is always some judgment required for knock limit. Two people can listen to the same engine and judge different knock levels, unless it is so loud that you can hear it just driving around without any microphone/amplification.
You need to confirm if this is in fact knock. It's quite possible depending on your fuel to have knock occur at this point at 0.6 bar boost and 15 deg. I'd try removing 3-4 degrees and confirm the knock does go away. It's possible you're hearing some mechanical sound that isn't actually knock. I'd also recommend cycling through the various frequency filters on the plex to see which works best for your engine. Lastly if retarding the timing doesn't change the noise then you can carefully add timing to purposely make the engine knock (obviously care is required when doing this and I'd recommend doing so at 2000-3000 rpm and low-moderate load) so you can distinguish between knock and mechanical noise.
I use 100 octane shell. I use 10kHz high frequency and I see that I listen more sound like knock. I change to 5kHz high band again, and I listen from 14 to 15 knock. I don't know if I help with that. I have not used to many different car, so I'm not familiar so much with knock monitor. This is the reason that I'm afraid. With 13 degree I'm sure that I don't listen anything.
I don't write that use a 2860 turbo, I believe it is important.
try to induce knock at very low load to really know understand how knock sound is and then compare it.
You can do what andre said too and remove 3-4º and check if there is "knock"