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dyno help ?????

Old Dec 24, 2004 | 07:50 AM
  #1  
h777's Avatar
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From: claymont delaware
Default dyno help ?????

a few months ago i dynoed my truck with the 100hp jets in.... at 4400rpm the graph drops from 396hp to 341hp real quick and my a/f goes from 12.2 to 9.75....my motor should be making power to 5300rpm .....could detonation be the problem ???? will detonation make the motor drop that much power and make the a/f pig rich .....bottle pressure was 1050 and i only had 92 gas in the tank........i have not been back to the dyno since but would like to redyno soon with the 125hp shot and 104 gas......what do you think???

heres the dyno sheet

http://mailcenter2.comcast.net/wmc/v...horsepower.jpg


.
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Old Dec 24, 2004 | 08:06 AM
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sfj
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were you running lean before the drop in power and then running rich or what but yeah detonation could definately cause loss in power
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Old Dec 24, 2004 | 08:13 AM
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From: claymont delaware
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Originally Posted by sfj
were you running lean before the drop in power and then running rich or what but yeah detonation could definately cause loss in power
a/f was 12.2 before the drop then it went to 9.75 a/f.....pig rich
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Old Dec 24, 2004 | 11:37 AM
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I've never seen detonation change the a/f ratio on my wideband. Sounds like the power drop is due to being too rich. You need to figure out what caused the richness.
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Old Dec 24, 2004 | 02:24 PM
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From: claymont delaware
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anybody have an idea on why my dyno jumped down in power???
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Old Dec 24, 2004 | 02:41 PM
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Link doesn't work. It wants a sign in.
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Old Dec 24, 2004 | 03:10 PM
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try this link for the dyno chart

http://mailcenter2.comcast.net/wmc/v...horsepower.jpg
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Old Dec 24, 2004 | 03:58 PM
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Originally Posted by h777
Still can't see it.
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Old Dec 24, 2004 | 04:26 PM
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Same thing ...
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Old Dec 24, 2004 | 05:25 PM
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From: claymont delaware
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sorry guys i dont know why it's not working........but can any of you guys tell me what could make the hp drop at 4400rpm and went from 12.2 to 9.75 a/f....could this be from knock retard?????

hp at 4400rpm was 396 then dropped to 341hp real quick then gradually went up to 367hp at 5400rpm
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