knock sensor location

[john carroll]

It is my experience that the GM sensors are quite 
directionaly sensitive.  Consistant mounting 
practice and materials are important.  

I believe that one stock installation of these 
sensors is on the front and rear face of V8 heads. 
GM did not choose this mounting location by 
accident.  The axis of greatest sensitivity appears 
to be perpendictular to the planes of both valve 
activity and piston slap.  It is threaded into a 
solid block of cast iron.   It may be well to 
reconsider the advantages of this location.  

For aircraft engines, I presently mount the sensor 
on a tab extending from the parting line at the 
center of the aluminum alloy crankcase.  The tab is 
.125 steel, attached by two bolts.  This location 
is necessary because the heads on the four or six 
cylinders are all seperate.  The parting line is 
the only location that is equidistant from each of 
the combustion chambers.  The best alternative is 
to attach a sensor to each head.  I get all kinds 
of noise but am learning to sort it out with the 
HIP7010. 

I suspect performance will be improved by making 
the tab more massive and by attaching it with more 
bolts.


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jac at wave.sheridan.wy.us
john carroll