Hey everyone,

I just came across an easy way to size your carburetor for your plastic fantastic.  For those of you old enough to know what a carb is, this really works.

Here is the formula

{CID x Max RPM} / 3456 = {CFM x VE}

Now the translation

CID is Cubic Inch Displacement

Max RPM is your redline as indicated on the face of your tachometer or, if you have modified or replaced your engine/internals, the new maximum RPM that you have experienced when "showing off".

CFM is Cubic Feet per Minute and is normally the unit of measurement to identify a carburetor

VE (I think) is an efficiency rating, it is normally .85

Remember:  When you input your numbers and come up with a figure from the left side of the equation, you must divide that figure by .85 and your answer will be a larger number.

Here's my equation - 327 x 6000 = 1,962,000 then divide by 3456 = 567.71 then you DIVIDE by .85 and your answer is 667.89 CFM

The article said that carbs are somewhat forgiving about being sized a LITTLE larger, so it's good to err on the side of caution.  In my case I should probably utilize a 700 CFM carb for my 1962 Corvette.  I presently have a 650 CFM Carter WCFB and am not going to replace it.

Paul