Ford 272 C.I. runs low 11's. Why do Mopar guys need 408's?

Big Block with aluminum parts and headers is about stock LA weight, and unless your a serious corner carver a weak argument for the ability for more power.
Who said anything about weight? Not me. I was talking about header fitment, engine mounts, ease of spark plug removal, trans has to change, etc. where a guy with a 318 could build a 408 and drop it in.