"LA" engine?

April 1963

Popular Mechanics

Chrysler is introducing a new thin-wall casting engine block for the
upcoming Model Year. The engine will be designated the 'LA' engine.

This engine block is lighter than the current 'A' Block, which was introduced in 1956 by Chrysler, and called the 'Hy-Fire 277'.

The new designed thin-wall casting engine block will be 50 lbs. lighter than the
current 'A' engine block.