The reason you do not desensitize knock!!!

Jpierro79

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No human ear can hear knock until it’s far beyond dangerous point.
This video at the bottom explains why you don’t do it. In a nut shell of removing a small amount of timing, adding more fuel, reducing boost or improving your fuel quality changes the knock reading it’s very real. Even going 1.5 degrees can cause more knock from a single cylinder to all 4 instead and multiple knocks. Just cause you modified the car does not means you created more noise, that it’s false.
This scenario is rare. Long tube headers on a car that previously had cast manifolds can add very little but it has to be an alteration directly attached to the block. Long tubes have thinner walls sound exhaust sound vibration goes back to the block and on many v8 the sensor is right under the exhaust manifold.

This is not true for the 10th gen civic. Fk8 or fk7. You don’t change manifold and even with the aftermarket turbo it’s not thin material like stainless tubing.
The most you gain will be in torque anyway not hp. False knock would occur regardless of testing conditions I explained above. You may have changed the down pipe or even if you have an upgraded turbo there is nothing that can send vibration back to the block like that.
turbos are made of thick steel and absorb the sound. Yes your downpipe is mounted to a bracket but that’s not enough to cause it. The only scenario you might remove some sensitivity is if with say 13 and 15 degrees you get the same single cylinder reading say a single occurrence on the same cylinder at both timing values. You still need a knock listening device to do it cause you can possibly have a faulty injector on one cylinder. Solid motor mounts don’t do it either. They can actually cause your chassis to absorb it instead. Your engine floats on rubber mounts like a drummers cymbal. Putting heavy duty mounts is like clamping the cymbal down. The noise gets reduced.. Maybe if you did a direct metal to metal engine mount you could possibly get a resonant frequency but super highly unlikely. Knock can wipe out a stock tuned car imagine at much higher loads. Detonation literally shocks the piston slamming it into the cylinder wall. That’s the part of the actual noise you hear. It happens way before you can actually hear it. The factory knock sensor uses the same exact sensor an expensive knock machine uses but set to a specific sensitivity. Subaru’s blew up many ring land cause the factory tune runs 14.7 afr till 4000 rpm at full boost on port injection in order to get their emissions status. Detonation from poor tuning blew many sti pistons apart. Yes it was weakest link but I’ve seen 1000 mile sti with blown piston but the same engine run for 150000 miles tuned on 370whp. Totally stock internals.
I made over 380whp 93 octane running stock knock sensor settings. No fuel system upgrades stock turbo. I’m now on meth and it’s significantly more power still on stock settings. Someone posted Running 17 degrees on 93 which is ludicrous. Don’t you think if there was that much room in timing hondata or prl would have done something with it. Especially when e30 car on about 14 max degrees does well over 450whp on small g25-550.


 

GraphiteAZ

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I knocked so hard on my vafc hacked turbo Accord that I quickly learned what it is.

You can hear it easily. It won't destroy a motor right away. But over time it absolutely will.
 

turbociv910

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Kock sensors are calibrated to listen to a certain FREQUENCY. You're comparing old v8 technology to ecus that can monitor multiple frequencies on a single sensor. Ive never seen an issue with bolt ons, but a loose component theoretically make enough noise to reach the knock sensor noise threshold.

1.5 degrees is a lot of timing change on these engines, and has already been noted by hondata. They/direct injection engines are much more "sensitive"

Simply gapping your plugs down will reduce the noise in the cylinder. The stock sensor is very good for noise capture...

Before plugs (3rd ged pull) 9500 to 12000 frequnecy ranges
2.jpg


after gapping (2ng gear spin then 3rd). Cylinder 1 is misfiring or knocking at the end of the run
1.jpg
 

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Kock sensors are calibrated to listen to a certain FREQUENCY. You're comparing old v8 technology to ecus that can monitor multiple frequencies on a single sensor. Ive never seen an issue with bolt ons, but a loose component theoretically make enough noise to reach the knock sensor noise threshold.

1.5 degrees is a lot of timing change on these engines, and has already been noted by hondata. They/direct injection engines are much more "sensitive"

Simply gapping your plugs down will reduce the noise in the cylinder. The stock sensor is very good for noise capture...

Before plugs (3rd ged pull) 9500 to 12000 frequnecy ranges
2.jpg


after gapping (2ng gear spin then 3rd). Cylinder 1 is misfiring or knocking at the end of the run
1.jpg
what gap have you tested? im planing to do mine to im on meth/94oct
 

fk8mike

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and also there are mods in hondata that remove 70% of knock window! not good
 


turbociv910

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Kock sensors are calibrated to listen to a certain FREQUENCY. You're comparing old v8 technology to ecus that can monitor multiple frequencies on a single sensor. Ive never seen an issue with bolt ons, but a loose component theoretically make enough noise to reach the knock sensor noise threshold.

1.5 degrees is a lot of timing change on these engines, and has already been noted by hondata. They/direct injection engines are much more "sensitive"

Simply gapping your plugs down will reduce the noise in the cylinder. The stock sensor is very good for noise capture...

Before plugs (3rd ged pull) 9500 to 12000 frequnecy ranges
2.jpg


after gapping (2ng gear spin then 3rd). Cylinder 1 is misfiring or knocking at the end of the run
1.jpg
Nice post thank you. You know me as jpierro79 screen name. I made original post here.

I just partnered up with fabricator and another tuner/builder. Now I’ve got dynojet access very close by. Therefore the screen name change.

Most don’t know knock listening devices use the same exact type of sensor already on the car. I personally haven’t seen it with bolt ons either. Only Chevy engines like lsa engine between the headers and overdriving a supercharger was the only time I found it needed. I can only speculate it had someone to do with resonance from a cross plane engine firing into long tubes. Could have been from overdriving the supercharger and the relocated belt tensioner. Hard to say.

Even motec has a special knock melody Le and requires course on setting up for knock listening. Dealers can not supply my this module without training.

lCurrently talking with the fabricator about larger MAF housing design. The fk8 seriously needs it.

I’m posting more on Instagram recently. Fk8_tuning_development on Instagram.

Questions about services emailed to [email protected]

 

 
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