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Discussion Starter · #21 ·
I finally got around to taking the upper off and taking a look inside. What I found was very light coating of oil on the intake ports in the cylinder head, definitely not a lot of oil to be found in there. The gasket between upper and lower had some oil on it as well, but there was no oil at all in the upper or lower intake manifold runners. One thing to keep in mind is that the car has been sitting without being started for about 5 weeks now, so whatever the oil might have been there could have leaked down by the valve. Looks like I will be pulling the lower intake off, and changing the gaskets in order to achieve better seals. I've got fresh plugs in the motor, so after another track day I will pull the plugs again and check to see if there is oil on them again. What's a little disappointing is that I was expecting #3 runner to be swimming in oil (since the spark plug was), and it looked same as the others, which leads me to believe that oil ring on that one is toast.
 

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Discussion Starter · #26 ·
I don't think PCV is an issue anymore. I reinstalled a stock PCV, because before it would just vent into a catch can. however one thing that I've noticed is that the amount of oil on the spark plugs is inconsistent between cylinders, #3 being completely covered in oil.

valve guides with excessive clearance, will not be seen in the runners
There was a bit of oil in the runners past the lower intake manifold gasket, but again, it wasn't much, probably because the car has been sitting for over a month. I will consider pulling the heads, since it's not that involving, but do you really think that valve guides could cause a cylinder to be swimming in oil?
 

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Discussion Starter · #28 ·
If it were a valve guide out of spec, what other telltale signs should I look out for, before I attempt to remove the cylinder heads? Would there be a pooling of oil somewhere, perhaps a build of of unburnt oil at the valve?
 

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Discussion Starter · #30 ·
Another thing worth mentioning. When I had it at the track last, whenever I would fire it up after a hard run session, it would shoot a lot of blue smoke out of the tail pipes, and eventually clear up. After a normal drive home though, I had to kill it and start it again when I was moving cars around, and upon a restart there was no smoke.
 

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Discussion Starter · #38 ·
Hey guys, since I've had the motor taken out and just taken apart the machine shop, I figure I'd update this thread. The cause of the oil consumption turned out to be 4 piston rings that were broken. The value guides were fine, the lower intake manifold gasket was good too. This is simply a result of either improper tune or overheating the engine at the track, causing detonation and thankfully only damaging the rings. The engine is still in the cleaning, I will know for sure what else got damaged, but this has been going on for years and years, so it's unlikely that it's recent. Hopefully the bore and pistons are OK, and it will be just a simple hone and rings/bearings job.
 

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What kind of rings were broken?
Compression rings? That should have showed up on the compression check if so.
 

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Discussion Starter · #40 ·
I'll find out for sure, but the machine shop said both. I would have thought that would show up on compression test as well, which is rather odd. All the tests were performed by my mechanic, so maybe I gotta have a conversation with him about that. I am happy that the cause of oil consumption is that obvious and blatant, I won't have to do any further head scratching. It would have been really bizarre if the engine would be taken apart only not to find any faults at all.
 
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