Detroit "Big-3" question?

[James L Miller]

I can't remember the specific time frame, but the 426 Hemi was done in around 4-6 months from "Go" to debuting at the Daytona 500 and finished 1-2-3. I recall reading they needed to make last minute changes to the cylinder cores as the walls were splitting on the dyno. I have a friend that has a very early 426 Hemi prototype block that looks like a 426 MW AAQA casting with the drain back holes added manually in the cores.