The CFM ratings on the those carbs vary greatly depending on who is talking about them.Generally speaking most guys run two of them to support about 180 hp.
Like the CFM guide mentioned above is only a static guide .The actual demands of the engine needs to figured out from real world experience on your particular engine.
And then there's subjective opinion
Some guys bolt a 600 cfm carb on a very mild 250 cube inline and say it runs like bear.Another guy might drive it and say it's a bogging pig and half the carb would be too much.
