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Old 01-27-2003, 07:11 PM   #1
chevjayfsd
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Demon CARBS<<<<<<

Well we got the motor back in the truck yesterday(Flat Cam) anyway, we went with our Demon 650 Cfm carb. Well we put it in and it just keeps backfiring through the carb....What the heck is wrong with it?? We set the time and moved it around but nothing. What do you think???

Holly Street Avenger???? Best way to go maybe.....

Thanks
Jason
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Old 01-27-2003, 08:27 PM   #2
mikep
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unless youve got the fuel level WAY too high backfiring though the carb isnt the carbs fault. Make sure your ignition timing is where it should be ( after verifying your float level ) ...Then its on to rocker arm setting ( likely ) or cam setup.


BTW cams dont just go flat without some help . What happened ? Are you sure your not repeating the mistakes that caused the flat lobe?
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Last edited by mikep; 01-27-2003 at 08:36 PM.
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Old 01-27-2003, 08:45 PM   #3
bigjimzlll
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what kind of intake are you running?..might be a vacuum leak..if you have a performer without an adapter. this can be a problem
Jim
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Old 01-27-2003, 09:19 PM   #4
Piston
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Double check your firing order.. its easy to cross 5 and 7. It will cause it to run a bit rough but also backfire through the intake.
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Old 01-27-2003, 09:23 PM   #5
Ackattack
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Might also check that the distributor isn't 180 degrees off.
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Old 01-27-2003, 09:24 PM   #6
HotRod929
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THis same thing was happening to me when I put my new HEI distibutor in. My timing was way retarded...check that again.

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