ok, ok, ok i've seen several topics close but i was wondering instead of cutting current valve covers, would it be smart to install crankcase vent kit?
i think this welds to collector on headers.......has anyone installed 1 before?

my motor
http://memimage.cardomain.com/member_images/5/web/737000-737999/737737_1355_full.jpg

The early blocks (1965 and before) used a road draft tube with a built in oil separator under the intake manifold and had a vented front oil fill tube with closed valve covers. First, what year block do you have? Second, I think you are confusing the vacuum evacuators that use the pressure drop caused by a special aftermarket exhaust collector to create a vacuum in the block; instead of using the usual PCV valve and a tube to the intake manifold. They are race only (requires an open uncapped exhaust to work) as they have no vacuum at idle and could ignite the fumes in a stock crankcase if used on the street.

Big Dave

The early blocks (1965 and before) used a road draft tube with a built in oil separator under the intake manifold and had a vented front oil fill tube with closed valve covers. First, what year block do you have? Second, I think you are confusing the vacuum evacuators that use the pressure drop caused by a special aftermarket exhaust collector to create a vacuum in the block; instead of using the usual PCV valve and a tube to the intake manifold. They are race only (requires an open uncapped exhaust to work) as they have no vacuum at idle and could ignite the fumes in a stock crankcase if used on the street.
Big Dave

ok my block is from a 71 vette, yea im not sure of the kit i need i know that my valve covers dont have any other openings for a pcv an i've been told that even though i have the cross-over breathers i need to pull excess combustion fumes from crank......wut other way can i do this?
as of now i have pcv port block on carb and i smell heavy fumes when the motor is ran not only from the open headers but from breathers. i know my valve covers are set up for track use but i've seen many vehicles run this set up with no problems....but i dont want anything coming up in future.......

found a bigger pic, might help....
http://www.speedwaymotors.com/eccStoreFront/product_images/500/545-68385_L.jpg

Thats different I have never seen that before.

I don't see how that's all that different than a normal vented valvecover, other than looking nice. Normally stock PCV systems have a PCV valve in one valvecover, and a breather (sometimes stuck into the air cleaner housing) going into the opposite corner of the motor. The engine is supposed to suck on the PCV valve, and that fresh air is going to be made up by air coming in the breather. That ventilation is supposed to help with emissions and sludging up of the engine from any blowby.

The setup you have looks like it'll allow excess pressure to be relieved, but there doesn't seem to be a way for the air to get sucked out (by PCV or other method) or have any forced flow of air through.

Your current breathers are a common race trick used by the circle track guys but they use them with a header evacuation system and open (unmuffled) exhaust. You could install a PCV valve in the back of a valve cover but unless you block off the front cross over tube it will just suck air in and across that one head. You could run a vacuum line down to the pan (with a PCV to prevent a back-fire exploding the oil pan) to suck out the fumes with your current set-up of breathers.

Big Dave