Engine loses power after launch

Old 10-01-2012, 04:57 AM
  #1  
lodilobo
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Default Engine loses power after launch

I'm running a Vega with a 750 h.p. small block with a 1090 Demon carb (96 jets). I use a trans brake, and come out at about 4500 rpm. When the car hooks well, and the front wheels come up, the motor will lose power instantaneously, then regain it....sometimes twice. I have a vent tube from breather to breather on the carb, and the float levels are where they should be. The car is going 9.50's @ 143, but I'm sure I could be in the very low 9's, if this problem goes away. There is really no loss of power or misfiring after the initial launch. Any suggestions?
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Old 10-01-2012, 05:44 AM
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fast75vega
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sounds like you need jet extensions in the rear of the carb :wink:
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Old 10-01-2012, 07:06 AM
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itsabird
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Originally Posted by fast75vega
sounds like you need jet extensions in the rear of the carb :wink:
x2
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Old 10-01-2012, 10:03 AM
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lodilobo
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Already has them.....thanks anyway.
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Old 10-01-2012, 10:23 AM
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fla1976
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Possibly a partially clogged fuel filter or weak fuel pump. What size fuel lines?
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Old 10-01-2012, 11:39 AM
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lodilobo
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Fuel lines are 10 AN......pump and filter are new...MagnaFuel pump w/ Aeromotive filter. I'm in the process of checking the fuel flow at the carb. That should tell me something. Also.....the regulator is new (Aeromotive). Fuel pressure gauge stays at 7.5 lbs.
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Old 10-01-2012, 05:01 PM
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TheYellaBrick
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Might want to check your fuel pickup in the tank....
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Old 10-01-2012, 05:59 PM
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mopar1968
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Fuel isn't coming out of the air vent and going down into the engine is it :?:
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Old 10-01-2012, 06:09 PM
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wrightway
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Are you running a power valve in the rear?
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Old 10-02-2012, 04:59 AM
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fast75vega
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Originally Posted by wrightway
Are you running a power valve in the rear?
that was gonna be my next question too ...... :wink:
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