I've pulled my slant 6 out of the barracuda and let me tell you, there is some serious weight to those things.
In Willem Weertman’s book Chrysler Engines
he gives a long description of how the Slant 6 was designed for an aluminum block,
but casting problems with the molten aluminum caused a “temporary” switch to cast iron.
Weertman claims the engineers eventually solved the aluminum casting problems but with production and sales going profitably a switch away from cast iron never happened.
