After going back and forth about whether or not to have the hole drilled for the oil fill tube in my new Edelbrock Performer RPM intake manifold, I decided against having the hole drilled.

Now, I know I have to get new valve covers but which type? I had spoke to a mechanic and he said to be sure and get covers with two breather holes, so does that mean the covers have to have 3 holes all together? Two holes for breathers and another one for the PCV valve? And what about the oil fill hole?

My 67 Camaro has a 350 and originally had the PCV running from oil fill tube in front of manifold to base plate of my Holley 4160 carburetor with an open element air filter.

Any help would be appreciated. Thanks,

Joe

One hole in each VC is all you need. On the driver side you plumb a pcv valve over to the case of your carb (vacuum source) On the passanger side VC you can put a breather or plumb it to the base of your air cleaner. Use a funnel and the most accessable of the two holes for filling oil, just pull the pcv out of the valve cover for access. Make sure you have a baffle on the pcv side valve cover or you'll pull oil into the combustion chamber and think you have ring or valve problems. (don't ask how I know!)

DJD,

Two questions.

One hole in each VC is all you need. On the driver side you plumb a pcv valve over to the case of your carb (vacuum source)
1. So on this cover I can just run the old line with the PCV valve from the valve cover to the base plate of the carburetor (where it was originally), right?


On the passanger side VC you can put a breather or plumb it to the base of your air cleaner.
2. Is there any difference/significance between placing a breather vs plumbing it to the air cleaner?

Thanks for the help! smile.gif

You've got it!! You want to create circulation throught the block. Manifold vacuum from the base plate sucks gases from the crankcase through the pcv valve in the valve cover. Fresh air is sucked into the crankcase through the other valve cover which is vented to the base of the aircleaner or a breather. I don't think there is any benefit from one over the other.