The reason I am making this thread is to let you guy know that at any time your plugs can take a dump. Last month I put a brand new set of NGK stock spark plugs in my car. On wednesday night my engine died. The spark plug in cylinder 3 ceramic broke and fell into the cylinder. Once the piston hit it, I believe it cracked. It then seemed to burn the piston on the side the electrode was pointed. I index my plugs. I have seen this before. It happened a friends firebird. It acts like a small welder that blows small pieces of the piston off. The metal from the piston is now stuck to the top of the cylinder wall.

I will be bringing the block to the machine shop Monday to see what they say. Hopefully since the metal is built up on the cylinder wall, they can just bore it one size over.

I am posting this from my phone. As soon as I get home I will add pictures to show the damage.

 

Almost forgot....these plugs had only 3100 miles on them.

 

Usually when pistons melt its from a lean condition. Not saying that it wasn't a junk plug. But more then likely you ran lean,

 

I think my car is actually on the rich side compared to most of the evos I have worked on. During spool I am @ 12.0 and at full boost I am between 11.0 and 10.5.

Not to say you are not possible right. I am having the injectors checked this week by BoostLab here in Tampa.

I did check the fuel pressure before I took the motor out. With out starting the car it held 45 lb with out an issue. So it would think that the it is still good. I am putting in the new aeromotive fuel pump once the car is back together.