Engine Help...!!!

[jononioo]

Ive been having bad luck with KA engines, my first one blew and the one i have in my s14 now has a bad rattling coming from the front and some really loud knocking from the rear part toward the transmission. Do you guys know anything about knocking coming from the back of an engine. My buddy told me that it may be caused from the fact that i didn't replace a bearing on the block or somthing like that. Another one of my friends told me that my rod my be damaged.... could somone with more knowledge please provide me with further insite on my problem. Thanks!