A very good point. Also I noted that you said the torque plates were solid, and since head castings have water passages and ports, you'd think they would distort a little. Now you,ve got me wondering how much things shift around by repeated heating and cooling cycles and how much of a tweak or set that they take.

The block I,ve just had machined is a 3970014 cast in 74 as I mentioned elsehere on the site the main bearing bores had shifted. Making an align bore and hone neccesary. I've allways gone by the adage "you want a good motor invest in machine work done by a good machinist." i'm picking these earlyer blocks because they have more iron in them than the later model chevy and mexican motors.

Now this block is not a green casting its 30 years old and has its first rebore to .030, bores cleaned up beautifully, now my question is, being seasoned and freshly machined is it still going to distort a little from occasional hard use.