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Why is my 408 a dog down low?

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Old Jan 12, 2007 | 02:04 PM
  #31  
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Originally Posted by Snake Eater
oh thats bad. I say add 5* timing and see what happens. Your timing sounds a little low to me. Also try increasing spark dwell 2ms.
Will do
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Old Jan 12, 2007 | 02:08 PM
  #32  
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Spark dwell on my tune did help out on my 60' times at the track. I did forget about that.
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Old Jan 12, 2007 | 02:12 PM
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Let us know how it goes, or how far you can spin the tires. LOL
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Old Jan 12, 2007 | 02:21 PM
  #34  
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Here's my current dwell table. Where should I make the changes? And why does increasing dwell make a difference?

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Old Jan 12, 2007 | 02:48 PM
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from 12-15v add 2ms.
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Old Jan 12, 2007 | 02:50 PM
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increased dwell creates better spark. With better spark you can run more timing without KR and get better throttle responce.
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Old Jan 12, 2007 | 02:53 PM
  #37  
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Cool I'll let you know how it goes.
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Old Jan 12, 2007 | 02:53 PM
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but if you increase it too much the coil packs will stay dwelling through multiple spark sequences right? say your dwell is 8ms but there are only 7.8ms between sparks? That wouldn't be good... I know there has to be HIGH rpm for this to happen but still. Also with longer dwell your coil pack life is lessened.
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Old Jan 12, 2007 | 03:00 PM
  #39  
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I think the culprit is your motor. It is useless and you may as well pull it out and hand it over to me. I will make it spin for you
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Old Jan 12, 2007 | 03:05 PM
  #40  
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What are the VEs on your cam? I bet that with the 9.5:1 SCR, and a cam of that size, your DCR is in the mid 7 range. I think that could make it sluggish down low.
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