Quote:
Originally Posted by Mikec10
Correct me if i'm wrong but wont a carb that's rated at lets say 800 cfm dump more fuel to compensate for more air?
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No, this is a common misconception. Say your engine can only draw 650 Cfm. And you put a Holley 800 with annular boosters so it gets a good signal and works as good as a proper sized carb. All a carb does is meter x amount of fuel for x amount of air. Under power that's about 13:1 13parts air one part fuel. And at cruise about 15:1. So with that in mind more air does mean more fuel but only if your engine can use it. So if its only pulling 650cfm of air through an 800cfm carb and you put on a 650cfm carb it will give you the same amount of fuel granted you tune them similar.
Now the question why you would put a big carb on a small motor? No reason othe than to not limit top end power but an oversize carb will kill low end due to less velocity through the Venturi, this velocity means the cylinders fill more and gives you better low end. Technically you can put a dominator on a stock 305 and not use any more fuel than a 500cfm carb. As long as your booster can get signal to the booster so it can meter the fuel curve.
There's a lot to read on for carbs and I could prob write you guys two pages of stuff on carbs easy but this gives you the basic idea. As long as you properly size the carb to your purpose you won't be disappointed with how it works
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