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Why do larger roots blowers use 2 carbs?

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Why do larger roots blowers use 2 carbs?

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Old 10-07-2014 | 09:41 AM
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Default Why do larger roots blowers use 2 carbs?

Curious why the bigger roots stuff use 2 carbs. Is one large carb possible? Such as a 1050 dominator in a 6-71 style blower. I have a 525sc with a weiand 177 and am trying to figure out if a blower upgrade is worth the effort.
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Old 10-07-2014 | 09:44 AM
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Fuel distribution I believe
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Old 10-07-2014 | 01:42 PM
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Fuel distribution is part of it. The main thing is when you start pushing through more air, you need more fuel and this can only be accomplished with 2 carbs.
I don't even think they make a single carb plate for anything larger than a 250/256 blower.
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Old 10-07-2014 | 01:54 PM
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I can tell you first hand the blower upgrade is worth it . Been there and done it.

Twin carbs doesnt mean more fuel. A 600hp engine tuned right should use x amount of fuel whether it has a single 1050 or dual 850s .

I have twin 850s on my engines. This summer i had a linkage problem causing the secondaries on one carb to not open all the way. I lost 1 lb of boost because of that. Roots like lots of available air
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Old 10-07-2014 | 02:35 PM
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More Air , Less Pumping Loss, and Better Fuel Distibution.
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Old 10-07-2014 | 02:42 PM
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I own a 1050 carb and a 6-71 blower, I was hoping to use that stuff .
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Old 10-07-2014 | 02:47 PM
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Fuel atomization plays a roll in it also. The size of the jets required to allow proper fueling if using one carb would be so large it would essentially be like raining fuel into the motor.

8 smaller jets > 4 larger jets
Smaller droplets = way more gooder
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Old 10-07-2014 | 02:54 PM
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Originally Posted by Old Navy
I own a 1050 carb and a 6-71 blower, I was hoping to use that stuff .
You can use it. I know they do make an adapter plate. I think youll find youll run out of carb before you run out of blower. Many guys have tried this since the 60s. Theres a reason 99 percent of 671 amd larger blowers run dual carbs. I woukd even prefer dual carbs on a 250 blower and its only about 60 percent of the size of a 671
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Old 10-07-2014 | 03:09 PM
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Don`t believe anyone , it`s all a Carb manufacturer conspiracy!!!!!!!!!!!!
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Old 10-07-2014 | 03:21 PM
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Is there a mathematical calculation used for carb sizing on blower motors?
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