Carb Size - BBC

Old 03-02-2008, 05:29 PM
  #31  
farrigno
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not interested in going to alchohol, but thanks for the replies, i sent patrick @ prosystems a tec sheet waiting to here back from him if my 1050 is not going to work...if i need bigger anybody interested in a 8896-1050-hp model it brand new/ may trade up for a 1150 or bigger model.
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Old 04-06-2008, 05:13 PM
  #32  
jaht1320
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Originally Posted by johnracer
Here's my 2 cents. The 1250 is probably a LITTLE to big, but since you already have it it's free. Right? It might actually run a little quicker and faster with a little too big carb, but consistency will suffer. A 1050 would be more consistent. JMO. I'd try the 1250 and see if it does what you want after proper tuning.....
Why would a bigger carb be less consistant? Just curious, I think mine is a little big too.
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Old 04-06-2008, 05:16 PM
  #33  
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carb that is! ops:
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Old 04-06-2008, 05:48 PM
  #34  
hammertime
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Originally Posted by jaht1320
Originally Posted by johnracer
Here's my 2 cents. The 1250 is probably a LITTLE to big, but since you already have it it's free. Right? It might actually run a little quicker and faster with a little too big carb, but consistency will suffer. A 1050 would be more consistent. JMO. I'd try the 1250 and see if it does what you want after proper tuning.....
Why would a bigger carb be less consistant? Just curious, I think mine is a little big too.
No in theory it shouldnt be it should be show less et change with more air.
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Old 04-19-2008, 11:47 AM
  #35  
jaht1320
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Originally Posted by hammertime
Originally Posted by jaht1320
Originally Posted by johnracer
Here's my 2 cents. The 1250 is probably a LITTLE to big, but since you already have it it's free. Right? It might actually run a little quicker and faster with a little too big carb, but consistency will suffer. A 1050 would be more consistent. JMO. I'd try the 1250 and see if it does what you want after proper tuning.....
Why would a bigger carb be less consistant? Just curious, I think mine is a little big too.
No in theory it shouldnt be it should be show less et change with more air.
So in theory a larger carb should be more consistant???
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Old 04-19-2008, 04:32 PM
  #36  
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If both are metering fuel correctly the larger carb should be more consistent and make more power. I would run the 1250 and let us know how it works. There tends to be some issues with the factory metering on 3-circuit Dominators, they tend to run fat at low and midrange and lean up top. If yours does, I can send you to a site to help you fix it.
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Old 04-19-2008, 06:11 PM
  #37  
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Guys,

Thanks for the thoughts. I was out racing today and happened to try 3 carbs. An old style #9375 1050, a new HP#7320 1150, and my HP#80532 1250. I jetted them similar and only took the time to set the idle speed and that was it. I wasnt sure if the jetting should be different based on the cfm so it wasnt the most thorough test....but anyway the 1250 actually gave me the best ET and MPH. Like I said it was an untechnical test but I had to try something. The 1050 felt like it ran out of steam near 3/4 track. It could be because I was way off on the jets (93 square on all carbs) or that it was to small. I ran 9.88 at 137 with terrible 1.50 60's due to a poorly prepared starting line (typical short time 1.33) If anyone has thoughts I would like to hear them. How would you jet this? I used the 1250 on the dyno and we had a hard time getting the back cylinders to be rich enough. I would figure the smaller cfm would provide better fuel distrubition compared to the 1250 but the results today were different.
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Old 04-20-2008, 04:56 AM
  #38  
jmarksdragster
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I have the 80533 1250, factory jetting is 97 for yours and mine and you should run 99 in back if you are lean. It may be a manifold distribution issue. You will jet according to carb size usually. The old 9375 is the best 3-circuit from Holley as far as metering and 93's are OK, but there are things you can do to the 1250 to help. Take out the intermediate bleeds (center ones) and put around .025 in the main air bleeds as well as jet it up. This will help an excessively rich bottom and midrange that is typical on 3-circuits. Invest in an AFR meter, dual O2 is best. I have a FAST but wish I had spent the extra for the Innovate system. If you find you are still lean up top, and good reading anyway, read the following. Mine has been converted to 2-circuit.
http://speedtalk.com/forum/viewtopic.php?t=9934
http://www.motorsportsvillage.com/fo...pic.php?t=3742
http://www.motorsportsvillage.com/fo...pic.php?t=3811
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Old 05-08-2008, 05:35 PM
  #39  
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Carb, go to BLP, (Bo Laws Products), http://www.blp.com/
but when you get it it will be a little rich. Gotta understand they are not going to sell you a lean carb and hurt your motor. extra jets will come in the kit. ONLY ONE INTAKE FOR A BBC (24* HEADS) AND IT'S THE PRO-FILER SNIPER.
http://www.profilerperformance.com/b...ntake-206.html
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