Head flow and power differences question / discussion

I am curious how much difference does let’s say 30-40 cfm of head flow make in HP.

Example: N/A small block 416 cu. 11.5 / 1 +/- compression

With a set of heads that flow 325 +/- compared to heads that flow 293 +/-

Everything else on the engine would be the same,intake,carb(s), cam,headers,ect.

Will the different heads be noticeable driving on the street or on a dyno only?

(edit)
What I am really trying to find out is, is there such a thing as too much flow and after a certain number, does the power curve go flat ? Or, is it always best to have the highest flowing heads available?

Let me know your thoughts and if I forgot mention anything.

Thanks in advance.


Another good post that we can all learn from.