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Knock Normalizing Mode G4X PnP 350Z


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I'm running into a condition where I sometimes in the same area of the map I get a small amount Knock ( false Knock ) on Cyl's 3 & 5.

This can be in low RPM after lifting off throttle (No Load) or at just 25% throttle & no Boost. Ignition Timing is very Low in this area & the other Cyl's are Fine.

The Knock Sensor on the VQ35De Block is Located Closest to Cyl's 3 & 5, and I have Kelford 272 Cams with dual Valve Spring . I'm sure there is a lot of engine and Valve Trian Noise, also have CP forged pistons & Carillo Rods.

So, now that I'm using Knock Noralizing Mode, is there a way to Lower the Values on Cyl's 3 & 5 Without retarding the timing more as I'm sure it's fause Knock. Note: I tested this with 104 Octane Race Fuel and Low Ignition timing values to Verify.

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What normalised knock mode does is compares the noise from the current combustion event to previous combustion events for that same cylinder.  If noise level is the same then the resulting knock level is 1.0, if there is more noise on the current event the knock level will be higher than 1.  

So if its showing knock on cyl 3 then for whatever reason, something has suddenly made the noise from that specific cylinder suddenly increase.  You may have to experiment with frequency or knock window to try to improve signal to noise ratio.  Our subaru test car does something odd around 2500RPM at light throttle on the highway so in that I just have knock disabled below that point, you may be able to get around it like that if it is a load or RPM that would never be knock limited.  

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Ya it's strange because one is at 9% TBS at about 3000rpm, in Low Vac a had been their for a few seconds at 0% TBS. I must have just put my foot on the peddle a bit. And just at that point I get a small Spike on CYL 3. I sure it's just Valve Train Noise.

And the other is in accelerating at 25% TBS LOW LOAD, 4750rpm, 18* Timing, 0 psi. It's just abouve the Knock Limit on CYL 3

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