I know that we found that your's was going to be thick enough based on the criteria of at least .125 for a normally aspirated engine, but I recall it as being real close and maybe even under that in spots. Which further raises the question as to whether there are really any blocks that could reasonably be bored to 94 mm.

What I can tell you, and this is not new, is that no one should do anymore than a 90 mm overbore without doing a complete wall thickness check. Most B20 blocks do
not have thick enough walls to bore to 92 mm.

Still open to question is whether there is some identifiable subset of blocks,
75/76 blocks for example, where the majority of blocks are thick enough for a 92 or 93 mm bore.
The basis for the original question was how to identify those blocks with certainty, so I could test some of them to see if this is true.

John
V-performance.com