its a 2.2 out of a vectra for the records sake

damage to ring land on cylinder #2
http://i29.photobucket.com/albums/c296/ ... CN0812.jpg
damage to head & valve above said ring land
http://i29.photobucket.com/albums/c296/ ... CN0813.jpg
http://i29.photobucket.com/albums/c296/ ... CN0814.jpg
some pics of the headgasket - you can see its gotten rather warped in places
http://i29.photobucket.com/albums/c296/ ... CN0816.jpg
http://i29.photobucket.com/albums/c296/ ... CN0817.jpg
http://i29.photobucket.com/albums/c296/ ... CN0818.jpg
im curious as to what people think came first - the presumed detonation or the headgasket?
personally im leaning towards the headgasket... it was replaced approx 6 months ago, but the head bolts were not. after all the discussion about torque to yield headbolts a few weeks ago i thought it might be an interesting example.