Engine loses power after launch

Old 10-02-2012, 04:14 AM
  #11  
lodilobo
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The carb is a Demon 1090 Dominator, and yes it has a primary power valve (6.5) and secondary (plugged) according to the specs. I pulled up on the Demon site. I know less than nothing about power valves.
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Old 10-02-2012, 11:42 AM
  #12  
oldandtired
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What is your vacuum at idle?
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Old 10-02-2012, 02:13 PM
  #13  
wrightway
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Originally Posted by oldandtired
What is your vacuum at idle?
In gear.
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Old 10-03-2012, 11:05 AM
  #14  
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Originally Posted by wrightway
Originally Posted by oldandtired
What is your vacuum at idle?
In gear.
Joe - if you're thinking what I'm thinking, the PV is cracking open.
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Old 10-03-2012, 04:24 PM
  #15  
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A 6.5 power valve sounds high to me for a 700 hp NA small block. but That should cause a rich low speed problem not what he has described.
Vent tube spill over and rear power valve installed in a hard leaving car sound like probable cause for symptoms described but sounds like he has the covered.
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Old 10-04-2012, 03:34 AM
  #16  
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I haven't had the chance to get an accurate vacuum measurement yet....just too busy at work. I hope to do it today. I have a feeling the power valve is the culprit, based on some of the input here. Thanks.
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Old 12-13-2012, 10:05 AM
  #17  
kevinmooreo1
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Check your coil for a crack. I had the same problem during launch.
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Old 12-29-2012, 07:22 AM
  #18  
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Not trying to be a prick, but are you absolutely sure (you've checked) that the jet extensions are in the rear, not the front? Been there, done that.....also check to see if you have a starter cable or other wire that might contact the header during launch. Haven't done that, but I've seen it....

Johnny
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Old 07-08-2013, 06:03 AM
  #19  
lg406
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Try replacing parts in the ignition system. Could be a loose wire.
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Old 07-08-2013, 04:33 PM
  #20  
markdunlap
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Default Engine loses

Had a friend who fought this type of deal.

Ended up being a lose wire in the steering column that was shutting off power to the MSD box for a second.
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