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So here is a quick run down on the car- 331 dart, trick flow top end with a v3 making about 14 pounds of boost and putting down 550 to the wheels.

I am currently still running the factory pcv and one breather. I blew the rear main seal within 400 miles of motor being built! Motor shop installed another rear main seal and within 60 miles I am getting a small amount of oil through the new rear main seal again. My question is what is anyone still running a pcv system with a blower? Have a check valve on the line from the pcv to intake, but I think I am building too much crank pressure and it not being able to release efficient enough! What setup are you running? My builder thinks the crank pressure is the issue not the rear main.

I know there are a bunch of knowledgeable people here, so I am asking for some advice!!!
 

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Discussion Starter #3
I think that is going to be the route I am going to take. Still need the pcv for emission testing, but the more I have been reading the catch can's might be the best route.
 

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Your pcv vavle needs to be one that closes during boost. The cheap $3 part store ones usually don't always close. Then you pressurize the crankcase. You are gonna also need a way to let the pressure off when in boost.

all in all, 14lbs is a lot of pressure on the rings. I never had trouble with a pcv and 9lbs-11lbs. 14lbs would do it though.
 

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So here is a quick run down on the car- 331 dart, trick flow top end with a v3 making about 14 pounds of boost and putting down 550 to the wheels.

I am currently still running the factory pcv and one breather. I blew the rear main seal within 400 miles of motor being built! Motor shop installed another rear main seal and within 60 miles I am getting a small amount of oil through the new rear main seal again. My question is what is anyone still running a pcv system with a blower? Have a check valve on the line from the pcv to intake, but I think I am building too much crank pressure and it not being able to release efficient enough! What setup are you running? My builder thinks the crank pressure is the issue not the rear main.

I know there are a bunch of knowledgeable people here, so I am asking for some advice!!!
if you search PCV

you will get tons of hits, then you start reading, and learn how the PCV works when properly designed into a system

if you have a breather with a PCV, that is a sign you do not know how a PCV system works........

so thoroughly learn it, so you can design something that will work for you.

a hint would be, diameter of tubing in stock form compared to something you have at cfm level you have.
 

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Ideally you should have metered, unpressurized air entering the crankcase. A check valve from the crackcase to the intake that won’t allow air to go from intake to crankcase when under boost.

Depending how your intake system is setup that may not be possible. Depending on what ECU you are running will determine how to solve it.

If running unpressurized metered air into crankcase isn’t possible. I would get a breather that scews into oil fill cap and some catch can packing material. Put the material in the fill tube and use the breathe cap for your air entrance to crank. You will need to use the check valve on the crank to intake.

However you will want to have a wideband to see what your AFR is doing. This creates un metered air going into engine causing a lean condition. It should not be bad but you have to see for sure.

The packing material will minimize how much oil is ejected onto covers and headers.

These would be the two options I would start with.
 

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Discussion Starter #7
Well I have a check valve from the PCV to the intake, also one breather on the fill tube as well. I am not getting much overspray in the engine compartment. The car is tuned and runs perfect as far as rich/lean goes. I am trying to learn how the PCV system works and create a system that will release the crank pressure accordingly and quickly.
 

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Discussion Starter #9
Thanks Indy. Put a pcv for the turbo coupe in, which helped the crank pressure. I am going to go that route and install a catch can as well!
 
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