Originally Posted by cudaman1969
Not sure but I’m thinking industrial, right thick on most cylinders at top .250 to .300+. Even at .120 over (426 + .060) still a lot of wall left
The last regular 413 blocks were made in 1965, Al used the industrial 413s at some point in his 426 Stockers unless he had some unbored 440s or 426 marine blocks.