knock counts and what to do next????

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Aug 9, 2003 | 10:17 PM
  #1  
After spending the better part of the day getting the car tuned everything seemed to be pretty close inline except knock counts. We used datamaster scanware and had the w/b 02 as well and were able to trim everything up excpet K/C. They are not around at partial throttle at all, just at WOT from 3K right through 5K where they fall off. They are strong enough to take out13 degress timing at times. Tried to calm it down first with taking timing out gradually with no luck. Tried adding more fuel before and where the knock came on but no luck. We eventually tried to pull out 10 degrees across the entire table but it had no change. I have tried searching all causes of false knock and am really wondering if thats what it is. Like I said we had the wideband when doing this so it was easy to see the added fuel and where the knock came on with the datamaster. Can anyone give me any ideas to try to see if I can pull the knock counts down. The engine should maybe need a little less total advance with the headwork/cam but like I said after removing 10 degrees it didn't change a bit, and this was after A/F ratio was dialed in and then enriched even more to try to see some results.
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Aug 10, 2003 | 05:51 AM
  #2  
Alternator bearings, serpentine belt, valve noise are all sources for false knock.

One way to CAREFULLY look for it, is disabling the ESC.
And then make a few mild runs and see if the plugs read detonation. Then progressively get into it harder, but you need to be good at reading plugs.

Or try using a 45d offset pipe fitting, and slightly deadening the sensor's response.
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