if my piston in my 455 are rattling in the block what caused this. I must be honest when I first go the car I was having a little fun with it because it ran very well when i FIRST GOT IT NO BLOW BY NO BLUE SMOKE NOTHING AND WOULD LIGHT UP A SET OF TIRES MOTOR IS BASICALLY STOCK HIGH RISE INTAKE HIGH PERFORMANCE, FUEL PUMP 12 BOLT POSI. iN PROGRESS OF BASIC REBUILT NOT TRYING TO GO BROKE $$$$$$ ARE HARD TO COME BY

 

Rattling is not good could be many things most are costly. I would check the heads for broken springs on the valves that would cause them to be hit each cylinder rotation. Next the heads need to be removed and the valves them selves need to be checked to be sure they are intact. hopefully the heads are the problem if it is the lower end is a lot more bucks. You didn't say how it was running when it started making noise. Is there blow by now ? Need more info.

 

engine has no blow by excellent power but just a little rattle but the engine is being torn down and going back with a mild rebuild