Fun Fact
That 300 run zone has been the CW for as long as I can remember
I guess that is what Bill Miller says and he sure is about 100 times smarter than I am but
I used to buy aluminum BME's used from McCandless or wherever I could get them--and run them in bracket 440's that saw 200 plus runs per year sometimes 300 runs a season--I never ever had one fail in that application
Have had some engines run for years with them well into the 700 run zone in a bracket 440
BME says make a few runs--resize them and run until you get enough $$ to buy more--he also says release the TQ on the bolts over the winter--I am SURE he is right about all that but just saying--I think we had nothing at risk but a stock block--If I had a high $$ block etc I would be much more careful
Sort of like Dad told me
You get a Shetland pony you tie him to the swing set and let him eat the onions in the yard--you get a thorough bred and you have to clean his oats, get him a goat for a barn pal, wash him like a new Porsche, etc etc

guess I have always had the ponys