Knock @ 1975 RPMs

[Barry Tisdale]

After changing heads to a set of 1996 models and installing a longer
duration Isky cam in my Syclone, I'm getting a 'false knock' between 1975 &
2075 RPMs.  Accellerating, steady state or coasting, all the same.  Goes
right to max retard (18°) in a very short time.  Major fueling changes in
this area have *no* effect. 

Obviously, this is of electrical or mechanical origin - no wiring changes,
so must be the sensor 'hearing' something relative to the cam or stiffer
valve springs that its filter circuits interpret as knock.

Anybody heard of this?  My first thought is to disable the knock sensor
below 2100 RPMs ww/ an aftermarket circuit.

Thanks - Barry
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