[lon]

Edelbrock uses this formula to size a carb on their web site.

street: displacement x max. rpm x .85 divided by 3456 = carb size for street apps
race: displacement x max rpm x 1.15 divided by 3456 = carb for race apps

on my car: 468ci x 5500rpm x .85 divided by 3456 = 633 cfm