ok, long story short, auction listed a 2004 mach 1 with a terminator motor upgrade.. cool. can see over 4-5000 worth of aftermarket goodies with an s.c. motor. no badge though.. ok, turned out it was a factory mach engine with a complete eaton swap.. everything needed was there and working, husr wasnt tuned.. sounds good, looked over and thumbed up by a ford tech. cool. so i bought it, beautiful screaming yellow, sounds great through bbk and magnaflow setup.. and thats where it ends... two days later i start to hear a faint knock. so being the guy i am, i pull everything, motor and tranny out the top, together.. cake.. pull it apart, all rod barinvs look good, 1 tiny speck on one of them,, no discoloration on the crank, ( forged crank) , no flakes in oil or fiilter..none i could see anyway.i havent pulled the pistons, but everything seems tight. gonna get an inspection cam tonight to inspect the cylinders... go from there.. question 1 would be, where else might this knock sound come from? it was very faint at idle, and almost sounded like my explorers timing chain when i shut it down,, kinda rattled... maybe tentioners? the chain is kinda loose, until you turn the crank, then will tighten up and release again.. opposite of the other side.. maybe chains stretched?? dont know mileage on motor, kinda at a loss as where ro go now. any insight guys??