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Discussion Starter · #1 ·
Hey guys. Since the motor was built, it's been consuming oil like crazy, an abnormal amount, maybe a full quart every 300 miles or so. Granted most of those miles are on the track, but that still seems a bit excessive to me. I can see it smoke through the tail pipe, it's pretty visible. I've had the motor checked out, and compression is still pretty decent (between 180-190 psi across all cylinders), leakdown is between 9-11%, and the motor still makes pretty solid power. Is it possible for all this to to be within spec, and still have a major oil consumption?
 

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That is excessive.
And you can see the oil being burned as evidence from the smoke out of the tailpipes.

3 things come to mind
1- valve stem seals/guides
2- pcv system
3- the rings have not sealed yet (unlikely)

Pull a few plugs and see if you have a buildup on any of them (or all)

Could also be a combination of the above along with an oil leak.
 

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A quart in 300 miles is a bit. Are you positive it’s being burned and not possibly a leak somewhere?
 

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pull the plugs and look at them, are they covered in oil?

what oil ring package did you use?

my guess would be valve guides and or oil rings, as compression rings dont really apply to oil control
 

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Discussion Starter · #5 ·
That is excessive.
And you can see the oil being burned as evidence from the smoke out of the tailpipes.

3 things come to mind
1- valve stem seals/guides
2- pcv system
3- the rings have not sealed yet (unlikely)

Pull a few plugs and see if you have a buildup on any of them (or all)

Could also be a combination of the above along with an oil leak.
1. Valve stem seals have been replaced, with no effect.
2. PCV system was converted to an oil catch can at one point, and while the catch can did collect something, it certainly wasn't a quart, not even close.
3. I am starting to suspect the rings at this point, because it seems like I addressed pretty much everything. I've had oil leaks before, but they were mere drips, nothing that would form a puddle under the car.

pull the plugs and look at them, are they covered in oil?

what oil ring package did you use?

my guess would be valve guides and or oil rings, as compression rings dont really apply to oil control
I will check the plugs a little later today, but from what I remember, they did look a bit oily last time I pulled and replaced them. The rings are part of the Eagle Specialty Product bottom end kit, and they are Mahle Plasmamoly.
 

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Hey guys. Since the motor was built, it's been consuming oil like crazy, an abnormal amount, maybe a full quart every 300 miles or so. Granted most of those miles are on the track, but that still seems a bit excessive to me. I can see it smoke through the tail pipe, it's pretty visible. I've had the motor checked out, and compression is still pretty decent (between 180-190 psi across all cylinders), leakdown is between 9-11%, and the motor still makes pretty solid power. Is it possible for all this to to be within spec, and still have a major oil consumption?
You can pull your intake to see if lower intake gaskets are leaking aka 1262’s . A leak down value of more then 5-6% on a new motor is high.
 

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Discussion Starter · #12 ·
You can pull your intake to see if lower intake gaskets are leaking aka 1262’s . A leak down value of more then 5-6% on a new motor is high.
I was planning on pulling the upper intake manifold to check and see if there is any oil on the intake ports in the heads (I think I can probably spot it with a flashlight. The heads are AFR 185CC Street Port and intake manifold is TrickFlow R Series. If the gaskets are leaking, which gasket set should I buy to replace them?
 

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I was planning on pulling the upper intake manifold to check and see if there is any oil on the intake ports in the heads (I think I can probably spot it with a flashlight. The heads are AFR 185CC Street Port and intake manifold is TrickFlow R Series. If the gaskets are leaking, which gasket set should I buy to replace them?
If you are running the 185 chances are the lower intake gasket is a 1262. Check your lower intake to head alignment, gaps should be even. I personally don’t like the 1262, but they align really well with the AFR Ports. I use the 1262S3 since it has a steel core and tend to hold better (IMO). Any over torque on the standard 1262 and they turn to crap. If your gaskets are leaking, you should be able to see oil in the runner when you pull the upper.
 

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Discussion Starter · #14 ·
Got a chance to pull a spark plug, just the easiest one to get to #4, and here is what it looks like. The plug itself is completely black, looks kinda greasy, and there is oil around the o-ring. I will pull and replace all plugs soon, and see if they all look like this. Next for me to is to pull the upper, and see if there is any oil in the runners, in order to eliminate the lower intake manifold gasket as a culprit.

 

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Discussion Starter · #15 ·
Ok, I've replaced all the spark plugs today. Here is the condition of the existing spark plugs, when I pulled them out, all numbered by the cylinder banks.





They all have a bit of what looks like oil fouling. The PVC has been reverted back to OEM setup, where as before I've had nothing, just venting into catch can. I still have to hook up the valve cover vent into the intake, because at the moment that vents into atmosphere as well. Looks like cylinder #1 and #3 are pretty bad, #3 being particularly oily. #1 plug was completely loose, I was able to take it out by hand, so it may be possible that #1 was external oil leak (valve cover leak) that leaked inside. Next up I will pull the upper intake manifold and inspect the lower ports to see if there is any oil build up in there, which would warrant the lower manifold gaskets to be replaced.

Any other thoughts?
 

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The valve cover “vent” line is not really a vent, it’s the fresh air inlet for the pcv system. It’s where fresh metered air enters the crankcase, and then circulates up through the pcv valve.

Without it, you are putting the crankcase under a vacuum, which is bad for gaskets and seals.
 

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Discussion Starter · #17 ·
The valve cover “vent” line is not really a vent, it’s the fresh air inlet for the pcv system. It’s where fresh metered air enters the crankcase, and then circulates up through the pcv valve.

Without it, you are putting the crankcase under a vacuum, which is bad for gaskets and seals.
That's good to know. I will probably route it anyway, just to get it all hooked up.
 

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pull the lower

stick a boroscope into runner and look at top of valve, caked oil, your valve guides are out of spec, or you sucking in oil from the intake tract.
 

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Discussion Starter · #19 ·
pull the lower

stick a boroscope into runner and look at top of valve, caked oil, your valve guides are out of spec, or you sucking in oil from the intake tract.
I've ordered a USB endoscope from Amazon, hopefully it will work with my phone. Once I get it I think just pulling the upper should be sufficient enough to get all the way by the valves.
 
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