i know the block will give out at about 450-500 but that about the internals what are they good to? say if some how my block was to stay together?
An over/under HP threshold on the stock block is utter crap science. Some people make 650 on them, others not so much. I split mine making only 260 RWHP. The problem is paper thin webbing and a 50-oz external imbalance that causes crank whip. Extended revs make the block flex, and the block splits with a crack starting at a main cap bolt hole and extending through the webbing up into the lifter valley.
Also, somebody explain to me how missing a shift breaks a transmission. It's unloaded at that point!