600 CFM, all I need. Check my math!

Per your question..........no, your math is not correct, it does not take into account of pumping efficiencies/inefficiencies. You are assuming 100% efficiency and that doesn't happen in an internal combustion engine with out alot of help......
There is more to carburetor selection than simple cfm numbers......air velocity thru the carb and intake are far more important.....for instance.....lets say you pick what would be the ideal carb for your engine based on your cfm calculation, you drive it and it seems ok, you race it and the time slip says the car ain't doing what you thought it should, friends and others at the track say put a bigger carb on it, you resist but eventually break down and try a larger carb, the car goes faster.......WHY??

A strong possibility is that the velocity of the air passing thru the ideal cfm calculated carb is too great and as the air-fuel mixture turns as it comes to the floor of the intake fuel drops out of suspension due to centripetal force and puddles on the intake plenum floor..........with the larger cfm rated carb, the velocity of the air slows down, fuel stays in suspension and the engine runs better. If you have several carbs, try them both, jet up/down as needed, watch your time slip, MPH means HP, jet up till MPH falls off, jet back to the faster combination.


Good luck