Knock sensor

[Sheltie2306]

Does anyone know of any external temporary knock sensor product that can be attached to the engine during tuning to detect detonation?

[Thumbs]

Two main systems, piezoelectric pressure transducer or fiber optic pressure transducer. The former is cheaper cos sensors are readily available from GM/Bosch/Denso (the usual suspects). e.g. Knocklink uses this.

 

http://www.link-electro.co.nz/knocklink.html&e=10342

 

For fiber optic pressure transducer, Kistler, Optrand etc make them but are much more expensive and require some "hacking" ;)

 

There's a few more methods but they will require surgery e.g. drilling into the cylinder itself or monitoring vacuum in crankcase.

 

Another method is ion-sensing to detect conditions prior to knock, and is used in the new E60 M5. Problem is that it gets too expensive at the hobbyist/grassroots level (asking price of 20K USD for basic setup).

Edited August 24, 2005 by Thumbs

[Sheltie2306]

Thanks.

[Nenekochi]

hi, care to elaborate more on wat knocking value is and how to read(anaylse) the value ? how to know wat the acceptable knocking range?

[Sheltie2306]

Hi, sorry, don't really understand your question. The knock sensor I use has recommended knock threshold values for my model of car. I will tune to remove all knock. For any other car, knock threshold calibration will be required from case to case basis. This is something I extracted from http://www.megasquirt.info/ms2/knock.htm which the method is applicable for any knock sensor setup: