318 race engine

I just got one of these 318 race engines and what I get out of it is there made to run hard off course be they can be boarded out up to 80 thousands over time so just short of throughout a rod out the side of your engine you can rebuild them time and time again I'm sure there probably made with a different steel that last longer that I'm not sure of but they are not just a myth.
Lefty, your writing skills show poorly. Spelling is off. While no one is exempt from bad spelling and poor diction, your excelling at it. After reading your post three times, I think I can answer your questions. If indeed it is a question and not just a rambling statement.

Please some blame spell check. Take the time to compose a well reading post and check spelling. Punctuation is an excellent addition to any written word.

The amount an engine block can be “Bored out” is found out through a sonic check that your machinist will perform at your request.

The stock blocks are constructed with a higher nickel content than the other brands of automotive manufacturers. The actual “Race blocks” are cast the with same material. I do not remember Chrysler casting them or saying the did with more nickel than a stock block. However, the race blocks are beefed up in areas that the stock blocks are not.

As said above and demonstrated below, check your block for these signs of it being a race block.
Was there really a 318 race block? LA or Magnum?
Yes. Many of the race blocks were cast with a bore just smaller than there listed 3.91. It was a rough bore. Needing finishing. The cylinders thickness is listed in the parts book. These race blocks ether have a “X” or a R followed by a number to identify them. Like below. There is also a casting number on the drivers side at the rear above the starter. This number can be looked up in the parts book to exactly what it is.
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