Tutorial: The best value detonation detectors on the planet.

[thehelix112]

Making Detonation Detectors for an Engine Tutorial

 

Parts Required;

3-4m of 1/2" rubber hose

Set of cheap plastic ear muffs

1/2" copper pipe

 

Tools Required;

Hammer

8-9mm drill bit

13-14mm drill bit

 

Step 1: Cut the copper pipe into one or two 10-15cm lengths, depending on if you want to listen to two points on the engine.

 

Step 2: Hammer 3-4cm of one end of each copper pipe flat.

 

Step 3: Drill a 8-9mm hole in the flatted section of this pipe.

 

Step 4: Bolt the copper pipe(s) to the engine. The ideal place for this is on the block, as high up the bore as possible (as close to where detonation occurs as possible).

 

Step 5: Cut the rubber hose into lengths and find a way to feed them from the engine bay into the cabin. As my heater doesn't work anyway I just removed the heater hoses and used these two holes in the firewall.

 

Step 6: Slide one end of the rubber hose onto each copper pipe you have bolted to the engine. Here is an example:

 

Step 7: Drill a 13-14mm hole in each side of the cheap plastic earmuffs

 

Step 8: Squeeze each rubber hose into these holes. Here is an example:

 

Step 9: Put them on and look like a doofus while driving. I believe mad1600 has an example somewhere of me doing just that.

 

Thanks to HSVSUX (he told me of this idea), and Umm_510 for hosting the pics.

 

Dave

[sims76]

Awesome DIY post....

 

Can you please describe the sounds that you hear. Or, will "you know it when you hear it?"

[proxlamus©]

haha thats bad ***

[big-phil]

wow I have all that stuff laying around

[Bernardd]

hey, great minds thing alike, i made the very same setup last fall.....works very well.

[thehelix112]

sim76,

 

You'll definitely know it when you hear it. You can hear each individual valve opening and closing which makes one particular sound, the sound of detonation is more high pitch and definite irregular (which is why elec det sensors have so much trouble figuring it out).

 

Dave

[datman]

would you guys be interested in a simple device tht you could wire to a used knock sensor taken from another car. It could give an audible or visual warning. Let me know and I'll knock something up...excuse the pun:)

[big-phil]

would you guys be interested in a simple device tht you could wire to a used knock sensor taken from another car. It could give an audible or visual warning. Let me know and I'll knock something up...excuse the pun:)

YES!!!! maby an L.E.D. light right between the the tach, and speedo. Let me know. I'll take one.

[Guest Mike]

would you guys be interested in a simple device tht you could wire to a used knock sensor taken from another car. It could give an audible or visual warning. Let me know and I'll knock something up...excuse the pun:)

 

Interesting... could you post some test results? I might be interested too.

 

EDIT: Became interested and did a quick search. I found one but it's overpriced, IMO. I'll look for a cheaper one. In the interim here's the one I found... http://tunertools.com/proddetail.asp?prod=TXS-KNOCK

 

EDIT#2: Making a visual warning light for engine knock may not be as easy as it would seem. After some research, I've learned that knocks change frequency depending on diameter/size/shape of the combustion chamber and the audio frequency can vary from 2-12 KHz. I guess the most accurate way is by listening as was originally posted in this thread. However, if one knows the appropriate frequency range for a given motor, building a visual indicator should be fairly straightforward, I would think.

[Guest Mike]

Here's a "knock sensor" with a light, heh, heh... http://www.hearmore.com/store/prodview.asp?idstore=1&idproduct=455&showall=yes

[datman]

It would be tricky to detect knock on all types of engines but not that hard for one type eg L6

Ill work on something and give you the schematics

[datman]

Not my design but this would work for an electronic listening/recording....you could record onto windows sound recorder

 

details here

 

http://home.netcom.com/~bsundahl/knock/listen/listen.htm#Recorder

[datman]

It seems that some cars have a filter system beofre the ecu, some Buicks and Saabs, this could be used to give a 0v-5v into the megasquirt

[thehelix112]

K.I.S.S

 

Dave

[datman]

I.i.s.s

[Sparks280zt]

I.i.s.s

 

Nice comeback, lol.

[Lunar240z]

http://www.viatrack.ca/

 

This can be used with MS or without.

[Brad-ManQ45]

KnockSense can utilize the stock ZXT knock sensor - which is tuned for the L28 already....

[Guest Mike]

It would be tricky to detect knock on all types of engines but not that hard for one type eg L6

Ill work on something and give you the schematics

 

Agreed... However, I currently have a 350 SBC w 10.5:1 and Edlebrock Performer RPM heads. Soon this will change to a SBC 434 with 11.5:1 pistons and AFR heads and will probably change headers too. I don't know if there's enough difference between to two motors to change the knock frequency much. Although I've read differently, it may be that knocks are nearly the same frequency in most engines. When I feel the urge to do some more research I'll look into it further.