Ah that makes sense. I think the slant 6 and its reliability was a result of its over engineered stout construction but also the fact that it was not powerful adds to longevity. Just like the beloved Honda 4 cycle motorcycle engines on the 1970s. Those single, twins and inline 4 cylinder SL XL and CB engines were not eye watering powerful but because they were low stress lower power they last damn near forever.

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.

Iron Slant with intake and exhaust is pretty close in weight to an LA motor.