Think i need my crank machined? (56k no)

the knock strarted right after i was able to put a load on the engine. i first noticed it on my way back from getting the car tunned and we thought it was the turbo… two days later the turbo broke. so we replace the turbo start the car up… let it idle for abou5 mins rev it up by the thortle and then i heard the same awfull noise again. As far as milies the internals probally have about 800 milies on them. if that. i bought them brand new and put about 800 milies on them.

i am really not sure what happend to them but i belive i might of gotten the wrong ones or something.