Knock Detection?

[nicksamaniac]

Just looking into knock detection tools, and was wondering what everybody uses, has used or has fitted permanent in there car, and what everyone recommends?

Has any body used the link G4 knocklink as a permanent early detection?

[89CAL]

My tuner uses the vipec knock sensors. Says they are great and he picks up knock long before anyone can hear it, even on a dyno

Think the link one is essentially the same. If I get a knock box. Think I will get the link

[denisonnd]

I haven't used knocklink. I have heard it is not 100% accurate.

One of the options is to use tables in your Link G4. You can get wideband sensor and AFR gauge, such as AEM with 0-5v input. Connect it to Link and give it some parameters. Something like (If RPM is above 4000, throttle at WOT or above 80% and AFR is more then 12.2 ==== boost cut).

That will not help you if you experiencing knock because of bad batch of fuel but if you have a safe tune then it's probably OK.

[Guilt-Toy]

i sold all my knock detection tools. i found that i could feel that something was wrong way before the engine gets noisy.

[Ben C34]

i sold all my knock detection tools. i found that i could feel that something was wrong way before the engine gets noisy.

Glad you didn't say the kmon was shit!

[nicksamaniac]

The kmon was the other system I was looking at, mostly due to the good price, but then thought the knocklink was maybe a good option as a permanent install.

Even though it's obviously not as accurate as the kmon, and more of warning light than anything.

[Guilt-Toy]

Glad you didn't say the kmon was shit!

The K-mon was good. the software was a little buggy at times though but it had some good filtering features and done its job.

how are you going with it ?

[89CAL]

My tuner used the link knock box with the headphones not using it through software or the ecu.

[sonicz]

Would a small amount of almost inaudible knock do much damage to an engine before you notice it and make adjustments?

I may doubt that as Almost ever day I hear a few family runabout cars and cop cars probably running on the cheapest fuel they can get knocking like crazy when they give power and they never seem to break.

Edited February 17, 2014 by sonicz

[KiwiRS4T]

Would a small amount of almost inaudible knock do much damage to an engine before you notice it and make adjustments?

I may doubt that as Almost ever day I hear a few family runabout cars and cop cars probably running on the cheapest fuel they can get knocking like crazy when they give power and they never seem to break.

The answer is yes. Your family runabout is probably not doing 7000 - 9000 rev/min with 25psi boost.

[nicksamaniac]

Just an update on this subject.

I've made a "kit" I spose you could call it, out of a sr20 knock sensor,(I think?-the flat bolt through the middle type)

Then I soldered a 3.5mm head phone socket to an old injector plug to connect to the sensor,

bought a $15 head phone inline amp and used a 3m headphone lead to go into the cab.

This is crazy good to listen to!

I've never heard so many vivid and different sounds from a running engine!

I'm not sure how it compares to pro level tuning tools but for $20 worth of bits and a sensor I had in the toolbox it was worth a shot to see if it worked.

I can even hear oil pressure bleed off when I shut the engine off, the only thing I need is to build a bandwidth filter to dial out background engine noise to listen for knock. And some sort of volume control.

But it was worth it and it works!

Edited March 1, 2014 by nicksamaniac

[Adriano]

Wait till you hear a lifter pump up at 7000 with valve float, you will think you have spun a bearing, bloody scary the first time

[GTSBoy]

@nicks

Good work. Good on you for having a go.

[Badgaz]

i have to say driving around with the headphones on is a completely different experience! even though this probably couldn't input to an aftermarket ecu its better than nothing and could be sold to heaps of other applications e.g stockcars etc.

[nicksamaniac]

It's an eye opener when you think you know your engine, you drive it daily and you can tell when something new makes noise,

Then you drive for the first time with headphones on! Wow-puts a whole New aspect on things!

[Badgaz]

for sure...shows you how disconnected the exhaust note is from the engine sound.

[Trex]

Could you post up a pic of what you did? I have a rough understanding and want to give it a go. I'm guessing you put it in the standard knock sensor location?

This would help you with the sound level

http://www.autospeed.com/cms/article.html?&A=0353

Edited March 2, 2014 by Stagea97

[Badgaz]

use the bolt holes at the back of the engine on the exhaust manifold side at the back....thats where we put one....i think that is usually for the engine bracket for lifting the motor out.

[nicksamaniac]

Because its running 2 knock sensors I mounted it in the middle under the inlet about the same height as the original sensor location.

I tried to get it close to the top of the stroke to pickup any knock. But my lifters are noisey after having the head reco'd, and the ecu was picking up false knock?

(it was in r&r off boost under low to no load, and thats what led to building this tool)

So it's new lifters on the list! And then go again.

But I spose it can be mounted anywhere your looking for noise, failing pulley bearings or noisy gearbox, diff center? Or maybe even close to suspension components.

[nicksamaniac]

This is the amp I bought from jaycar for about $15.

this is an adaptor I made, 3.5mm socket to 3pin duetch plug, with shielded speaker cable.

and this it on the engine, 1 pin is signal and the 2nd pin is shield/ground.

I have the signal bridged to both left and right on the 3pin plug so I can hear on both sides,

the adaptor will allow a 2nd sensor to be wired in, so I can run front and rear detection. On both ears independent.