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any of you guys ever use the valve covers with the 2 tubes on one side with the clamp on breathers... and bare on the other valve cover??? are they good on a street motor or should you use a pcv style valve covers???
 

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Hates: Liver. Loves: Diesel
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They're typically used on circle track cars but I see no reason not to put them on a street engine. The PCV system meters ventilation by the valve, not the breathers, so as long as you have adequate breathing (which you would in this case) you should be fine.
 

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Curtis is correct
Circle track cars have the vents on the left side of the car, since centrifugal force makes oil go to the right. Two big vents are a good idea, especially since a pcv doesn't pass much volume and blow by can exceed the pcv capacity.
 

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What about valve covers that have no holes for breathers, can they be used on the street? I really like those Dart aluminum ones
 

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Canadian Charlie said:
What about valve covers that have no holes for breathers, can they be used on the street? I really like those Dart aluminum ones

Sure, but the crankcase must have a filler tube/ vented cap somewhere to let air in when the pcv sucks and blow-by pressure out.

Remember seeing any "old" 50s-60s engines that had a oil filler neck on the intake manifold? They usually had a "road draft tube" and and after '62 a pcv to pull the blow-by out of the crankcase.
 

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If your street car has to turn right as well as left you might consider covers with a transfer tube between them at the front and a pair of breathers in the tube - ala IMSA,SCCA etc. 'Course it all depends on how hard you want to corner. Smog laws can be an issue too.
 

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xntrik said:
Remember seeing any "old" 50s-60s engines that had a oil filler neck on the intake manifold? They usually had a "road draft tube" and and after '62 a pcv to pull the blow-by out of the crankcase.

Here is a picture of my '56 272 Y-block with the oil filler neck in the intake pan. It has a road draft tube on the other side.



Here is the bottom of the road draft tube:

 

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BBC valve covers

I've got a 396 in my 67 Nova it has 1 breather on each side no pcv my problem is the blow by is causing oil to come out of the breathers on to my covers. My motor has about 800 miles on it roller rockers, roller cam etc. Probably around 550 HP any recommendations on how to eliminate the oil seepage.
 

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boobert said:
I've got a 396 in my 67 Nova it has 1 breather on each side no pcv my problem is the blow by is causing oil to come out of the breathers on to my covers. My motor has about 800 miles on it roller rockers, roller cam etc. Probably around 550 HP any recommendations on how to eliminate the oil seepage.

Breathers dont really accomplish the same task as a PCV. They just filter the incoming air so that the PCV's vacuum doesn't draw a dirty charge in from the outside air, and it keeps oil from getting all over the motor. Install a PVC, you could even use two if you like. Sometimes motors that are pretty aggressive can use more ventilation. And yes, a PCV will help with blow by a bit by sealing the rings from the lower end of your motor. If there is damage to the rings or bores, however, you may not notice a difference-

K
 

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You really need a pcv to help evacuate your crankcase fumes and pressure. Install the correct one and your problems will probably disappear
 
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