I guess this is a question for those that rebuild for a living or are a machinist. Is there a rule of thumb concerning cylinder wall minimum thickness? Most don't like to go more than .060. After that some say to sonic test,x-ray,or ultra-sound to see if it's a boy or girl
But what does the machinist base his decision on after the sonic test? Is there a set thickness that he won't under? I'm sure many on here know the answer for drag race motors but what about street driven motors,whats the minimum?