The biggest difference is lobe separation and overlap, efi needs minimum 110-114 LS the bigger cams need wider LS, a carbed car can use a cam with narrower LS thus increasing power to a point. You can use a a "carb" type cam if you are using a programmble type efi as you can run it in open loop at idle but if it is a closed loop system then a cam with 112+ LS is required.
my 67 vert
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