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

I never tried to rain on anyones parade. I've "built" 170 cu in Fords and Chryslers. In reality they both exceeded our expectations in both power and mpg. No, they would never run with a big block, but both were very sweet running motors. I ran a 273 because that was what I had so I tried all kinds of combinations. The power is in the heads, cu in dials in the rpm where that power is made.