477 BBC HIGH RPM MISFIRE

Old 04-26-2009, 04:56 PM
  #1  
bajaboat32
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Default 477 BBC HIGH RPM MISFIRE

I have been fighting this for long enough... 477 BBC Dart pro 1 heads, Roller, 13:1, BG 400 pump (new), Quick Fuel 1050 Alch, MSD Distributor ignition.
Between the 1 -2 shift the car started popping slightly, steadily got worse. EGT was reading high. Put larger jet in carb. Kept getting worse as time went bye. Don't race alot so a few weeks go bye between attemts to cure. Thought it was a fuel delivery problem. Ordered new BG 400 pump and 4 port reg. Installed but no cure. Got up to almost 200 jets and still had hot EGT temps. Winter came a I said I'll see you next year.
Ordered new valve springs and installed. Went out today and problem still there. Any other things I am missing? I am probably looking over the problem so don't be afraid to mention some silly questions at this point.

Thanks in advance.
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Old 04-26-2009, 05:33 PM
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hammertime
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What kinda fuel pressure ?

Also when you were putting bigger jets in the carb was the egt going higher or lower ?

What fuel ya use ?
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Old 04-26-2009, 06:34 PM
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bajaboat32
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I have 8 to 9 lbs of fuel pressure. When I started changing jets, The EGT did not change or got worse. I am i at 1335 degrees and only running 1/8 mile.
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Old 04-26-2009, 06:35 PM
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Sorry. I use V/P alch.
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Old 04-26-2009, 06:38 PM
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hammertime
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Originally Posted by bajaboat32
I have 8 to 9 lbs of fuel pressure. When I started changing jets, The EGT did not change or got worse. I am i at 1335 degrees and only running 1/8 mile.
changing jets didnt move the egt at all ? I assume you checked the float level already ?

Which VP fuel the normal m1 or m5 ?
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Old 04-26-2009, 06:52 PM
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bajaboat32
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Yes float levels been checked. I guess M1 on the fuel.
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Old 04-26-2009, 07:42 PM
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hammertime
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increase the fuel pressure some and see what happens, could be a bad gauge and be lower then actual ?
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Old 04-27-2009, 05:52 AM
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bajaboat32
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Did that. Put a second gauge on it and it is set now just before it runs past seat.
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Old 04-27-2009, 06:01 AM
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hammertime
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what high side chip does it have in it ?
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Old 04-27-2009, 06:09 AM
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bajaboat32
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Set to 7600. But now I can't even get to the shift point to make it shift it pops so bad. Shift point is at 6500.
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