225 slant 6

Consider this as well, the slant six was designed on blueprints as an aluminum engine. There were some made. So, imagine how much meat was designed into that engine to be aluminum. They did not change the casting process to thin the metal out when they switched to cast iron. So that means the cast iron is much thicker than it needs to be in the slant six. This can quickly be proven by how much the slant six heads can be milled. They can stand a .100" cut and not even flinch. Likewise, they can usually be bored .100 over. At least the 75 and prior. I don't know if they thinned them out after 75, but I wouldn't be surprised. I think the early engines with the steel cranks would be pretty much unbreakable as a turbo motor. That is to say, as long as it was prepped correctly.