Well, I believe I found the culprit:
Notice how the metal ring has started to separate and pull back from the cylinder side, leading it to split.
Unfortunately (or fortunately depending on how you look at it), I uncovered another problem while inspecting the cam and rocker arms. The #3 and #4 exhaust lobes were all munched as were the rocker arms themselves. Looked like they had been hit by a grinding wheel that's how bad they look. So, I emailed EB and got a quote to replace all this stuff, and decided that I might as well go for the RV cam (the 270 version) while I'm at it along with new valve springs.
Darin-- tell me about this cam! Do you need to do anything else to the engine to make it run well? My motor is all stock, and all I have is a 2-1/4" cat back exhaust. Does the AFM need to be adjusted?
Also, concerning the head-- should I have it professionally cleaned, or should I be able to do that myself? I'm sure I can rent a valve spring compresser and completely disassemble the head. I just want to make sure I get everything super clean. I can inspect the head for flatness at work-- we have a surface plate here.
I'm sure I'll have more questions. You guys have been very helpful, and I appreciate it. So that's the update for now.
Fugly!
I havn't seen many blow the fire ring like that. Are you way high on compression? Is there any chance the head was over torqued?
Also a cautionary tale: Last time I saw that (a few months ago in a 2F-SE) it was because the rod bearing was worn and the piston ws smacking the head. The F-ring just was in the way and got smashed to smithereens (much, much worse than your gasket- it was seriously FUBARed). Junked the whole car. And there was surprisingly little noise. It sounded like a valve ticking.
Be sure to double check!!! EZ to do without pulling the pan- just look for evidence of collision on the head and piston (shiny aluminum) or crank that sucker up to TDC and see if it peeks up over the block. Cheap and easy if you find and fix a bearing before it goes critical.
Usually on a blown gasket, I see a coolant path
over the f-ring.
About your cam- good eyes! most people overlook it.
About EB's cam- haven't tried it yet, but his other customers rave about it, and they can't all be wrong.... <img src="/forums/images/graemlins/lol.gif" alt="" /> Seriously, EB's good people. You'll be happy, I promise.
About your AFM, Darin's right. Leave it be. Exception: If you
know for a fact that you're running too lean, then one click rich. Remember- you have a feedback ECU controlling mixture. The O2 ought to be able to feed info to the computer regardless of any cam you install and be fairly accurate. I mean, if you really want to get into high-end tuning, then play away. But remember the consequences if you get it too wet in there!!!!
