Oil Consumption LS2 427
I have not yet had a chance to test if the Cartek catch can has solved my problem, but I am hoping it will.
The PCV system on these engines is a fixed orifice. When GM decided on what size of fixed orifice to go with, they may have based their decision on how much vacuum was being produced on the intake side. With an aftermarket motor (especially something as large as a 427) the amount of vacuum has probably been significantly increased. Thus, the amount of suction on the PCV system would also increase, which would draw more oil mist into the intake. When I installed my catch can, I also removed the throttlebody to look inside of the intake. The inside of the intake was all oily yet the intake only has ~2000 miles on it.
Take a look at your spark plugs. If they are all oily (and oily the same amount) the PCV is probably the culprit as the chances of all of your valve seals being bad (and being bad the same amount) is a bit slim. If only a few are oily, or some spark plugs are a lot more oily than others, bum valve seals are probably the issue.
I have not yet had a chance to test if the Cartek catch can has solved my problem, but I am hoping it will.
The PCV system on these engines is a fixed orifice. When GM decided on what size of fixed orifice to go with, they may have based their decision on how much vacuum was being produced on the intake side. With an aftermarket motor (especially something as large as a 427) the amount of vacuum has probably been significantly increased. Thus, the amount of suction on the PCV system would also increase, which would draw more oil mist into the intake. When I installed my catch can, I also removed the throttlebody to look inside of the intake. The inside of the intake was all oily yet the intake only has ~2000 miles on it.
Take a look at your spark plugs. If they are all oily (and oily the same amount) the PCV is probably the culprit as the chances of all of your valve seals being bad (and being bad the same amount) is a bit slim. If only a few are oily, or some spark plugs are a lot more oily than others, bum valve seals are probably the issue.
My plugs were exactly the same. Spark end itself was reasonably clean but the threads were oily. I think it is like you said. The oil is burnt off of the spark plug tip.
If all of your plugs look the same it could be one of three issues.
1) Your heads were ported to such an extreme that the rocker bolt pathway actually pierces through. Oil is moving past the rocker bolts into the intake path. <-- Unlikely. To check this a rocker arm bolt is removed and a visual inspection is done to see if the bolt hole pierces through the head (it is not a blind hole anymore).
2) All of your valve seals have popped off of the valve guides. <-- Unlikely. To check this, remove the valve cover and take a look. If the valve seals have popped off they will be riding high on the valve stem. You can see this even with the valve spring still on.
3) PCV system is the culprit. <-- Likely. Install a catch can that eliminates the valley to the intake PCV, and the passenger side valve cover to the throttlebody PCV. Also install a oil cap breather. The majority of catch cans, still route back to the intake and throttle body. Look for one that does not.
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My plugs were exactly the same. Spark end itself was reasonably clean but the threads were oily. I think it is like you said. The oil is burnt off of the spark plug tip.
If all of your plugs look the same it could be one of three issues.
1) Your heads were ported to such an extreme that the rocker bolt pathway actually pierces through. Oil is moving past the rocker bolts into the intake path. <-- Unlikely. To check this a rocker arm bolt is removed and a visual inspection is done to see if the bolt hole pierces through the head (it is not a blind hole anymore).
2) All of your valve seals have popped off of the valve guides. <-- Unlikely. To check this, remove the valve cover and take a look. If the valve seals have popped off they will be riding high on the valve stem. You can see this even with the valve spring still on.
3) PCV system is the culprit. <-- Likely. Install a catch can that eliminates the valley to the intake PCV, and the passenger side valve cover to the throttlebody PCV. Also install a oil cap breather. The majority of catch cans, still route back to the intake and throttle body. Look for one that does not.
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If you already have the valley hose capped off that would leave the line from the passenger side valve cover that is running to just before the throttlebody.
As a temporary test (before running out and buying a catch can) you could do the following. Install an oil cap breather, and plug the PCV line running from the passenger side valve cover. Drive the car for a while and see if the oil consumption ceases. Make sure you have an oil cap breather as the crankcase needs a way to vent.
Some people simply have a downward facing hose hanging off of the passenger side valve cover and downward facing hose hanging off of the valley cover. Thus any oil simply drips onto the ground while you are driving.
The drawback to any system that does not connect back to the intake is twofold. First, without a vacuum souce (e.g. intake) the contaminated mist is only removed from the crankcase as crankcase pressure "pushes" it out. Secondly, there is the environmental concern. Part of the PCV system's purposes is to recycle the contaminated oil mist back into the combustion chamber so that its burned.
Which valley cover used does play a huge part, because different valley covers can have different different sized PCV orifices.
Which valley cover used does play a huge part, because different valley covers can have different different sized PCV orifices.

The Carteck catch can has three ports. Two of the ports come with 90 degree elbows and the the third port has a plug on it. The fitting are interchangeable and Cartek provides a hose that you cut to the lengths you need. You have a variety of plumbing paths to pick and you simply pick the paths that you like best.


