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Link G4+ Knock Control

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So I watched the webinar a few times to get a decent handle on how to go about setting this up.

I have a built EJ25 with a bit of piston noise due to the clearances.

when I first installed the ECU I fiddled about with it a bit and maybe turned the KNK Internal to "ON".

The tuner did a couple of run in tunes and then a dyno. After looking into all of this further it turns out the knock control was left on with no filter applied and according to the I trim tables it is pulling 3 deg out in the 1300-5000rpm range as it is always seeing a 1000 knock count. Now I'm pretty sure he used a fairly safe generic timing map as he tunes Subarus almost exclusively. I wondered why it didn't make the power I was expecting from the engine/turbo/heads/cam combination.

So if I'm on the right track here it is probably safest to log the engine noise as is then pull the 3deg out of the 1300-5000 range and get some ears on it and start adding it back in.

A couple of questions here. The link offers suggested frequencies and it is giving 6kHz for this engine and sensor. Does that normally work for this engine?

And what is a good starting point for the gain? Can I fiddle about with that before I set the frequency to get it into the ballpark? It is currently default set at 200.

The issue I've got is the knock gear I'm using it GIZZMO K-Mon and it seems to have a lot of static which make things a bit hard to hear. So I want to be pretty close when I start off.

Thanks Rob W

If the tuner wasn't aware the knock control was active and not configured, then it could very well explain the poor results you encountered. 6 kHz is a reasonable starting point based on the bore diameter, however I'd also try the 2nd harmonic and see if you get a clearer signal to noise ratio.

The gain needs to be adjusted until you're getting a signal level at high rpm with no knock present in the range of approximately 300-500. It will vary from engine to engine and also depend where the sensor is located. 200 is almost certainly way too high and I'd expect to be somewhere in the range of 2-10.

I found the GIZZMO K-Mon to be next to useless and sent it back. I couldn't distinguish knock at all and I seem to recall I too was having issues with static. I'd recommend looking into either the Link G4+ Knock Block or the Plex Knock Monitor V2.

Thanks Andre. That is good information which helps a lot.