Calculator for figuring out correct carb size.

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willburr76
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Calculator for figuring out correct carb size.

Post by willburr76 »

Hi i just got this off another website thought it would be interesting for those always wondering!!!

D = K x Square Root(C x n)

where:
D=carb diameter, in millimeters
K= constant between 0.65 and 0.90 (determines the smaller and the biggest diameter to be tested at the specific engine)
C=cylinder displacement, in cubic centimeters
n=RPM at peak power/1.000 (be realist, dreaming only will make you try carbs far bigger than the correct, with results below your needs
(C)50ccx8(n)= 400 (the 8 being 8000 rpms)
Square root of 400= 20
20 × .7(K) (the constant) = 14mm

Hope this helps some of you wondering
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burnt_toast
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Re: Calculator for figuring out correct carb size.

Post by burnt_toast »

nice calc! found on accident trying to figure out some stock carb sizes, figure it deserves a bump :bump:
projects galore :nerd:
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