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Nelson tune logged need advise!!

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Old Feb 5, 2005 | 04:36 PM
  #1  
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From: VACAVILLE CALIFORNIA
Default Nelson tune logged need advise!!

I am having a lot of problems with knock in one area only. I only get knock when I goto WOT from approx. 30 mph and it kicks down to 1st gear from 2nd. It doesn,t knock right away. I can watch the boost build and it begins to knock at full boost and high rpm (5000 or so). I also am hearing a noise. It could be knock but it doesnt sound like it. It sounds like a rev limiter to me. It also feels like it is hanging in the gear, like it doest want to shift.

Could the knock be caused by the rev limiter? Maybe the fact that its hanging in gear is causing the problems. My LTFT are around 960 to 970 at WOT. I also saw as muck as 1000 when I floor it in 2nd gear. This seems pretty rich but it runs ok. Any suggestions??

I
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Old Feb 5, 2005 | 04:55 PM
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Have you tried to turn the boost down 1 or 2 lbs to see if that helps? What are your intake temps with the frame mounted IC?
Before I installed the shift kit, mine would seem like it would "hang" before shifting to 2nd, and it was not consistant on the shift.
Now with the shift kit and no TM it shifts nice and quick.
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Old Feb 5, 2005 | 04:56 PM
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How much timing is it seeing at those RPM's?
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Old Feb 5, 2005 | 04:58 PM
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Also your 02's being 960-970, may be a little rich, but its safe, especially if you tow.
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Old Feb 5, 2005 | 05:24 PM
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From: league city texas
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i was seeing the same thing with my tune. we took it down even to 18 degrees timing and it was still seeing knock. it was seeing it in the same cells. we found that it is false knock since it was not audible. even with a genises it was found to be false as well.
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Old Feb 5, 2005 | 05:26 PM
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From: VACAVILLE CALIFORNIA
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My timing at the rpms it has knock is 11 deg with 7 deg of KR. My intake temps are right around 97 deg. This would put my timing at around 18-19 deg. This is at 6 psi boost. I also tow a lot so I have my 02s pretty rich.

Could the rev limiter sound cause false KR? I dont know what Allen has mine set at. Ill know soon I sent him a message..
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