Engine Condition Review During Head Gasket Change

[Sam280Z]

I recently blew the head gasket on my ITB turbo L6. I'm pretty sure that the root cause was an assembly error by the idiot (me) who put the motor together. I assembled a 1.5mm MLS head gasket from layers from two gaskets, one new and one used. Out of ignorance, I put two shims together and two embossed layers together instead of alternating them. It ran like this for over a year, with no symptoms except extremely slow coolant loss. Last week it finally gave out and combustion pressure clearly was getting into the cooling system. The motor hydro-locked overnight. I did a leakdown test and found that cylinders 3 & 4 leaked between themselves and the coolant (see videos in album linked below).

 

In the album I have pictures of the piston tops and combustion chambers before and after cleaning. 

 

https://plus.google.com/photos/110595327894846974778/albums/5819204301794009809

 

To me it looks like light detonation has removed the gloss from my JE pistons . I also need to work on my throttle synchronization as evidenced by the varying shades on my exhaust valves.

 

 

I thought I'd get the opinions of those with more experience than I before I reassemble. 

 

Thanks,

Sam