I was in the process of replacing the head gasket on a 95 E320 sedan and got everything all back together idling the engine when all of the sudden it stopped with a load clunk. I have done about 90% of my tear down and so far I have determined the failure seems to be related to the timing chain being too tight causing the front of the intake cam to break off. I have already verified at least two bent valves and what I am wondering is how sturdy are the pistons. I have not pulled the head just yet but assuming I only have a couple of divets or dents in the pistons will I still be OK. My assumption is based on looking through the spark plug hole and sending air through the cylinder where it obviously came out of the intake port but I did not get anything out of the crankcase. Basically at this point I am trying to determine if fixing the valves will be worth my time or should I just figure the engine is a total loss? Again any help I can get would be great any other surprises or things I might be missing would be great.