Was driving my car one day and heard some rod knock. Decided to try and get it home, but the noise got louder and the car started to behave strange, so I pulled over and had it towed. I finally got around to pulling the engine (6 months later) and this is what I found. It looks like just 1 piston made contact with the head (and maybe a tiny nick against the valve). Other than that the other 7 pistons look normal...any idea how just the one piston could do this?

Engine is a 2002 block that supposedly only had 5k miles on hone, rering, and bearings. 2006 799 heads with BTR titanium valve springs and retainers, TSP cam 235/40 duration, 635-609 lift, 111 LSP, TSP chromoly pushrods, Fast 92mm intake and TB, LS7 lifters, ported SLP oil pump, Improved Racing oil pan baffles.

I was thinking I might have run low on oil, but now I'm not entirely sure.

 

 

I did find some bearing material in my oil when I drained it. I assumed that I spun a rod bearing, but wasn't sure since I haven't seen head contact like this from it before.

 

i put had rod bolts not torqued properly actually loosen causing the piston to graze the valves and dust off the carbon on them. When i took the heads off and put #8 at the bottom of the bore i was actually able to push the piston down with my fist a tad bit further causing the a little clack noise as the rods sloppyness tapped the crank journal. Same story though, shifted into fifth at low rpm and bang, knocking noise. I got lucky. This was an old 5.0 though and i probably just forgot to tighten it or didnt make a second pass on it. Live and learn.

 

whats the spring look like on that valve?