I will get flamed on here for this , but I have always been a big believer in people over carbing street machines...

I just watched the Edelbrock video..

They suggested there 500 cfm carb for 350 and under.. 600-650 cfm for 350 to 454 cubes..

The Edelbrock video said to use anything larger ONLY for a much larger engine or a race specific only engine...