Mopar 318/275 HP vs. Chevy 327/275 HP 'L-30'

Well............

Since the SB Chev came out in 55, that makes the first LA nearly 10 years later. You "wuda thunk" that in 10 years Ma would'ha analyzed what could'ha been made better, but in many ways they didn't. In many ways the LA series was just an extension of the old Poly block, including "Not Enough" head bolts.