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

318willrun said
Correct. An aluminum headed Low Deck weighs about identical to a cast headed small block

I think it's lighter. The difference between a fully dressed 360 and 440 with stock parts is only about 150 pounds. People think "big block" and automatically think big weight when it's simply not true.