knock link

[A80Avant]

i wont be in Greece for the next 2 summers at least,so no problem! I will be in the UK!,better fuel quality and not so much hot temps!!

if i were to stay in greece,i would install it in no time!

[gnutz2]

ever heard of that before?

http://www.thor-racing.co.uk/Knock_Link-LNK_KNK_LNK.asp

you think it is useful?needed?

I`ll add this Diy version to the list.

It uses a led and a buzzer but the main advantage that i can see is that you can adjust the sensitivity too. So if youre mapping the engine in the low rev band you can turn it right down to hear the slightest knocking and the opposite is true.

I like the way the guy linked the pot inbetween the 12v+ and the timer signal to adjust the sensitivity (clever ******). And i suppose if you know how, you could run a fun a few 555`s with gradually greater resistors to run the traffic light effect like the other knock sensors.

Anyway, i bought all the bits from Maplin for about £15. I`ll let you know how i get on

[gnutz2]

If i added the link it would help


http://users.california.com/~eagle/knock.html

[EspenW]

Interesting DIY build.
I've got the KnockSense in my Golf, and I'm about to install the TurboXS KnockLight in my RS2. The big advantage of the KnockLight is that it takes an RPM input as well, and adjusts sensitivity based on that. The KnockSense does not have this feature, and goes off at high RPM, due to engine noise. The KnockLight also doubles as a shift light.

[gnutz2]

Ok, i`ve made the knock sensor cortroller (on my second attempt) and it works suprisingl well.

With the sensor clamped in the vice and the sensitivity turned fully up, a light tap on the vice with a hammer sets off the light and buzzer for 0.1 seconds (this time can be changed if wanted). If the sensitivity pot is turned all the way down then quite a substantial hit on the vice is reqired.

My next plan is to link the signal from this timer to an adjustable time circuit (another 555 timer), say 0.5-2 seconds. And put this signal into one of the analogue inputs on my DTA ecu, this can then retard the ignition and or lower the boost by an ammount determined by me.
The time this happens can then be adjusted until the car pulls out of the detonation danger zone.

I dont imagine this simple system could be as effective as the bosch OE system but it will give peace of mind that any real knock or phantom noise will be dealt with.

I`ll post some pics of the system and let you know how i get on

[gnutz2]

Knock Box



I managed to mount the buzzer inside the box and drill a hole in the lid to tidy up the installation. Theres a toggle on the front to mute the buzzer and a test button on the rear and theres a small holein the back to adjust the sensitivity on the pot .

[gnutz2]

Ive been running this device connected to both the knock sensors for a few months now and i can tell you that it works very well and can indicate knock before the ear can hear it.

A bit of time needs to be taken to set up the sensitivity on the pot but it works great after that.

As far as the different frequency at different rpm scenario is concerned, my turbo spools up at 4000rpm so it's the 4000 to 7000 scale i'm intrested in and it works fine in this bracket.

The only thing i would change, is the device is to sensitive to voltege change so a simple voltage regulator is needed to flatten out the supply and calm the device down Then the sensitivity can be turned up even more. And i heve allready done this