Stop discarding good 340 engines ! !

Sonic tests don't lie. I think the cost of building an engine has driven people to check out the blocks more thoroughly prior to dropping 4k on parts and machine work to complete a short block. Generally I use .040 or less blocks for my performance builds. For instance,
I wouldn't build a 400 block over 4.380". Having had cylinders split at 4.375" on a 4.34" OE bore has made me cautious and skeptical. Most of the 340 blocks I have tested or seen the results from are similar to a 400 block - all over the place and not expected to be highly uniform. The main diff between the 340 and 400 block is about .030-.050" in measured cylinder wall thickness favoring the 400.