The FE was made in a lot of displacements for a wide range of applications. They had low rise, medium rise, and high rise heads. Incorporating some of the valve cover area may have been to given them the flexibility to manufacture those different types of heads with very different intake port designs.
HaHaha, yes they are Heavy...
It is interesting that this style has not be discussed, since it is unusual
But I said I had my thoughts, and here it is
I think compared to the Y Block the engineers placed the Cam higher in
the block, so the engine had shorter push rods less weight and Mass to move
Any thoughts on that?