Knock Headphone Setups?

[Mitco39]

Hey guys,

I am looking to find what you are all using to listen to knock on the engines you tune. I have made a knock listening device for the Nissan cars I have tuned and it works well but I am looking for other ideas on the least intrusive way to monitor these engines for knock. I want to be able to listen along side of what the knock sensors are saying to rule out any false knock (or vice versa). I would prefer not to have to hack any harness's or cause any irreplaceable damage to the vehicles being tuned.

I am currently tuning a LS1B controller however I would like to have a solution for all the EFILive supported controllers.

If anyone cares to see the device I made here is a link to the instructions to build it, while it would work I would imagine on these domestic vehicles I have to splice into the harness (or use a patch harness) to listen in.

https://uprev.com/documentation/Knoc...n%20Device.pdf


Thanks in advance.

Mitch

[Mitco39]

I guess knock detection is not a big deal for guys on here? Incase anyone ever finds this via search I decided to go with this setup.

http://thetuningschool.com/product/plex-knock-monitor/

[joecar]

It's a big deal to me, I use a modified Chassis Ear, but it seems to pick up too much noise.

I'll see what the engine shop uses.

[pinstripebob]

So if you make or buy knock phones, do you watch a log and listen for knock at the same time and make a note of false/real knock?

Sent from my Nexus 5X using Tapatalk

[Mitco39]

I like to listen to the engine to determine if the engine is detecting false knock and go from there. Without headphones you are at the mercy of what the ecm thinks is knock never knowing for sure if its safe to desensitize the sensors to stop what you think might be false knock.


I was joking about not finding it important, lol. Everything I found on this plex setup is good so I am curious to see how it goes. Shitty part is you have to swap out the factory sensors but it does get around needing to worry about wiring that way.

[joecar]

So if you make or buy knock phones, do you watch a log and listen for knock at the same time and make a note of false/real knock?

Sent from my Nexus 5X using Tapatalk

Yes, on the dyno, as you hold a cell in the VE or MAF table, you listen.

[pinstripebob]

That makes sense. Would knock phones be usable on the street?

I've attached a photo of some knock retard I'm seeing periodically, as well as the log and tune it came from for reference. In the picture, I had about 5.5 degrees of knock retard spike and decay over 5 seconds.



GTO_November_14_2016_2.efi
Garrett_GTO_tuned_20161114_1.ctz

[pinstripebob]

Thinking about this some more, would it be possible to pull the signal from the factory knock sensors similar to Mitco39's setup in post #1 and split that off to his amplifier? Then from the amplifier (or some "black box"), split to Mitco39's headphones as well as a 0-5V analog signal into the Flashscan V2? Then you could chart what you hear, correlate it to the data the ECU has, and determine action taken from there?

[Mitco39]

Yes you can do that, thats how I have my Nissan wired up to listen to it while its running. The issue with this is if you are doing customers vehicles you dont really want to be cutting or splicing into their wiring harness. But if it is your personal vehicle then this is what I would exactly do.

When I took the car down the Vegas last year I would put the knock headphones on with every tank of fuel and set the boost accordingly lol. If I heard knock id turn down the boost till the knock stopped for that tank of fuel. Overkill but I like to go as fast as possible lol.

[joecar]

That makes sense. Would knock phones be usable on the street?

I've attached a photo of some knock retard I'm seeing periodically, as well as the log and tune it came from for reference. In the picture, I had about 5.5 degrees of knock retard spike and decay over 5 seconds.



GTO_November_14_2016_2.efi
Garrett_GTO_tuned_20161114_1.ctz

Increase the decay rate (so it decays quicker), then when it comes back, observe if it is a single spike, or a series of a few or more spikes.