Did some more math y'all
(all math is using 100% efficiency)
For a 307 to need a 750 cfm carb, it would have to spin 8500 rpm.
For a 307 to need a 600 cfm carb, it would have to spin 6750 rpm.
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For a 350 to need a 750 cfm carb, it would have to spin 7400 rpm.
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