frito1

iTrader: (12)

and the plug looks like this!




I haven't torn it apart yet but I have a pretty good idea what it looks like with small flecks of alum. on the plug. So now what do I do next? I have a nice bunch of parts. What would you do with my parts? What shortblock would you apply them towards? If I go too big, my cam, heads and headers will soon be undersized. This one was supposed to have 27k miles on it out of a '04 GTO. And it looked it too..... BTW, NA all the way!

98Camarod

iTrader: (43)

I'm guessing the ringland came apart....

frito1

iTrader: (12)

What causes this? I haven't overheated it. Did it go lean? I did have some oil mist from the PCV. Did the oil cause it (detonation)?

Beaflag VonRathburg

iTrader: (176)

I can't see the picture at work because of picture filters. Usually, no compression = ring failure, ring land, or destroyed pistons. The usual cause of this is detonation.

DaddySS

Do a leak down as your first step.

Did you drop the plug or was it closed like that?

frito1

iTrader: (12)

LOL, a guy at work said, "you dropped that plug, right?" I showed him the nick on it. It has been hit by something... ie, chunk of ring or piston. I'm positive with what I've seen that I will hear air come whistling out of the dipstick tube. I poured some oil in the combustion chamber and came up with 25psi vs the Opsi I got with no oil.

DaddySS

That's a fair indication that you have ring problems and while I don't see how a bent valve would do what you're seeing, I would want a little more proof before I decided - take the heads off or drop the engine.

frito1

iTrader: (12)

Yeah, I will drop the engine and pull it apart on a stand before I start ordering anything. I guess I should have added that the rest of the plugs looked like new so the excessive fouling would have been proof I didn't drop it after I pulled it out.

frito1

iTrader: (12)

Does the stock LS1 PCV system create enough oil mist to detonate and cause piston failure? I'm trying to make sense of this so it doesn't happen again. I will have a catch can next time but not sure that is what caused this....

The #7 intake runner is dry. The rest were plenty oily of course. So that means #7 hasn't been sucking for some time. I really think this piston has been dead for a long time.