[Dragncar]

Originally Posted by hurryinhoosier62

I know of two ‘66 389 blocks that had cylinder walls less than .090 thick.

Whitmore told me the 66 398s had thin bore and a lot of comebacks.
It was one of the reasons the 67 400s are said to have thick cylinder walls.
I have a 2 bolt 67 400 that is .060 over. I would like to get is sonic checked just out of curiosity. But I do not think anyone does it around here.

[Joe-Touring]

Originally Posted by Dragncar

Whitmore told me the 66 398s had thin bore and a lot of comebacks.
It was one of the reasons the 67 400s are said to have thick cylinder walls.
I have a 2 bolt 67 400 that is .060 over. I would like to get is sonic checked just out of curiosity. But I do not think anyone does it around here.

Heard this as well. I have a 67 400 in work at another machine shop that will be my “nice” engine. I’ll post the sonic numbers up when I get em. Hopefully that block is good or I’ll have to start searching again…