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What Are The Advantages Of A 2 Barrel Carb Over 4 Barrel Carb And Disadvantages?

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Anonymous answered
I have seen in some cases a two barrel equipped motor create more torque than a identical 4 barrel equipped motor.2 barrel carbs are more reliable unless they are a Holley which just suck anyway in both versions for street apps.Racing on the other hand 4 bbl all the way and a Holley dominator is the way to go if your engine can use it.don't over carburate either.Read up about volumetric efficiency and know the average street car is usually only putting out 80% of its potential or less. There is a formula to figure out the cfm rating your engine requires but I can't remember it .Google automotive math and you should find the formula.Remember think with cubic brains not dollars .The saying "speed costs how fast do you want to go "is utter B.S.I have built ten second cars for under two grand.Including buying the car!use your head.
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It depends on what your objective is.

All things being equal a 4 barrel will flow better then a 2 barrel and give the engine more power. So in this respect a 4 barrel is better.

But a 4 barrel carb will be more complex (more parts) so will be more expensive to buy/build and will be more difficult to keep in tune.

However in one respect a 2 barrel carb may be better. With smaller venturies a 2 barrel can be more closely controlled and will give cleaner exhaust.
thanked the writer.
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Anonymous commented
It's mainly about CFM. Why couldn't a 2 bbl have the same CFM as a 4 bbl? Some 4's are spreadbore meaning the 2 front barrels are small and the 2 back bores are larger. The 2 larger back ones ONLY open up when a vacuum signals them. A 2 barrel doesn't rely on a vacuum to signal add'l CFM. That's the scenaio I saw at the race track one day. For most of us we enjoy the smoother transition of a 4 barrel so that we only use the back barrels when our heavy right foot demands it.

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