Pitting in combustion chamber

[KFred 513]

So I've been porting my 2g head and noticed some pitting in the #4 combustion chamber. Milling the head will get rid of the issue on the surface, but in the chamber Ill have to smooth it out.

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Was this caused by detonation? Should I be worried about the gouges on the head surface? I have plenty of thickness left, but the machine shop will probably have to take ~.020 to get rid of it all. That would put me below MIN thickness, so I would rather have them mill it just to true it up so I can have it milled again in the future.

Also wondering if I should do any work in the CC? I've heard rounding the sharp edges can reduce hotspots. Just looking for some input on what has been successful.
Thanks

 

[BogusSVO]

No, that is normal. Most have it to some extent, this is for the sides of the combustion chamber.

The pitting in the deck, something got in there and bounced around for a bit.

 

[KFred 513]

Thanks for the info bogus. One of my spring seats were broken, and another was about the break off. Could be the culprit.

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[talonalex92]

There is no possible way a piece of a valve spring shim (broken or not) could make it into the combustion chamber. At all. Did you find any broken valves? Something made its way into the intake tract and got sucked in, or maybe a bit of a spark plug could have broken off. Hard to say.

 

[KFred 513]

There is no possible way a piece of a valve spring shim (broken or not) could make it into the combustion chamber. At all. Did you find any broken valves? Something made its way into the intake tract and got sucked in, or maybe a bit of a spark plug could have broken off. Hard to say.

Good call. I didnt think that one through Haha. All the valves were fine. Always run a filter too. Oh well. Damage is done, luckily nothing major.

 

[DSMnoobsause]

I have seen the Porcelain of the spark plug break and run around the cylinder.

 

[BogusSVO]

Check your turbo fins.

That or part of the spark plug are about the only options. Well a chunk of ring maybe, but you would see piston damage.

For the spring shim, good chance that broke when someone forced a head stud washer in 1 of 4 locations.

 

[KFred 513]

Turbo is fine, cylinder has one vertical gouge, about .005" deep, and not wide at all. I'm not too worries about it. Could be damage from a long time ago that a previous owner dealt with.