[mrlaw]

Today I build myself a *knock headphone*.The design is so simple ,it took me 30 minutes total

here is what you need :

ear defenders
1 foot of copper pipe 3/8"
about 10 feet of hose (fuel hose will do )
a 3/8 " T piece
2 3/8" -1/8 npt barb fittings

Drill the defenders in the lower spot and tap the holes to 1/8 ntp
fit the barb and slide the hose on them, the connect both hoses to the T-piece.

Flatten the copper pipe and drill a hole in it then bolt it to the head (or block)
Slip the hose over the pipe and over the T piece aswell
done:

Does it work? Yes it does

You can clearly hear any noise coming out the engine
You will clearly hear the motor Knocking .The sound is very distinctive from other noises!
So before you go out and buy the Turbos XS tuner pro or the HK$ knock amp try this .It cost me about $40

Lawrence

 

[^Trickster^]

Excellent write up lawrence, its about time you put our conversations into practice, only took you a month from you first thinking about it to building it lol

Im going to build a set this week if i get time of course!

Graeme

 

[JJ]

Haha...lol, this is a sweetest invention ever Lawrence!!! :thumbup:thumbup
I'll try that one of these days after I finish up my engine rebuild.

JDMR2TT

 

[Turbo_PePe]

3 hoeratjes voor Meester Lawrence :cheer2:

excellent work man.
gonna make my self one , right away.

btw , will thinner hoses also work ?
it seems youre's are quit thick.

i'm thinking of using vacuum lines which are like 4mm.

 

[^Trickster^]

I think thinner walled lines would give a less clear volume? The thicker the line, the more difficult for the noise to escape as opposed to travelling all the way to your ears

Graeme

 

[Turbo_PePe]

mmh ... i might connect some 2 inch thick wall hoses to the earphone ...
i like a high volume of sound

 

[Akane]

This is very ghetto Lawrence.......... I'm disappointed, yet facinated!

 

[flyboy]

This was posted on EFI101 as well. Good find! It works just as well as knock mics that cost hundreds. How do I know? I have used both!!

Some notes I have found useful:
-Use hard lines. This attenuates the sound much less
-Use the absolute smallest length of hose you can. Longer hoses attenuate the sound more.
-Obviously avoid kinks or sources of diameter reductions.
-Attach it to the block. You hear less valvetrain noise that way. I put mine just under the exhaust manifold on one of those huge, oddly unused bolt holes.

 

[JLDMRDOS]

wow very impressive!!

 

[kosh]

RickyB uses one when tuning all of his customer's cars at Turbohoses. Works brilliantly.

 

[huck-jai]

bumpin an old thread. I'm gonna try this. =)

 

[sflmr2]

For a little variation on this theme, using some easy to find parts, see this thread: LINK

 

[supercharged111]

Back from the dead! Has anyone ever tried both of these? I'm curious if the earphone one works any better. As for the more ghetto of the 2, how about using aluminum or steel tubing? I can get those easier than copper. How about more hardlines? I'm thinking of bolting this to the firewall side of my block on my 4A-GZE and running a permanent hardline inside the car so I might only need 2-3 feet of rubber hose. Is 3/8 or 10mm the ideal size? I could easily go bigger if 1/2" would be better.

 

[Domp5586]

thats the hottest ish i ever seen-I personally use to use a Long Screwdriver plastic to listen but this looks bad Ash..nice-I will have to build one and whip it out on people..nice job..

-Dominick

 

[supercharged111]

thats the hottest ish i ever seen-I personally use to use a Long Screwdriver plastic to listen but this looks bad Ash..nice-I will have to build one and whip it out on people..nice job..

-Dominick

Long screwdriver plastic?