motor knock

u may need oil change, headers messed up, r it may be yo valves

if the knock seems to get louder when you keep it at a certain rev. then it could be the timing chain but that shouldn't happen on a new engine if it sounds more like a tic it could be your lifters but it could be alot of things if the knock sounds like its coming from the bottom end of your engine you should get the car looked at by a pro.