Pcv valve-yes- or- no

[geneo4116]

[Sok im running a 350, small cam,headers 4 barrel,automatic,300 gears, question do i have to run a pcv valve,valve covers have no place for it,really dont want to drill holes in covers,what are the pros and cons,dont really want to run breathers either,im i asking for trouble

 

[TiredIronGRB]

It has to breath somewhere, either a breather tube or PCV system...if you don't it will make it's own.

 

[geneo4116]

I guess that makes sense,thank you.

 

[CR55]

Ditto!! You'll have oil everywhere if you don't....CR

 

[donsrods]

I have heard of people drilling through the intake manifold into the lifter valley and venting them that way. It involves some aluminum welding and fabrication, but isn't impossible.

My 331 stroker had the same problem, I bought a nice set of Edelbrock finned aluminum valve covers that had no provision for venting or for adding oil. So I added a pair of Moon breathers, one to each side, and the lid is removable so I can add oil too. Now that they are on I am glad I had the problem because I think they look pretty trick and racy.

Don

 

[zzrodder]

If you don't have a breather, how are you planning to put oil in it ? Like the other guys said, you gotta do it - it's unhealthy for your engine to try to keep that contaminated air inside, causes sludge buildup, contaminates the oil and like they said, oil leaks, like from the front and rear main.
If you swap to an early intake - pre 68 - they have the hole at the front for the breather / fill tube and you could drill at the rear of the manifold near the distributor to put in a bung to plug in a PCV.
Another option is a newer air gap type manifold, you could drill a hole for the breather right behind the thermostat and use something cool like Donsrods showed. OTB and O'brien Truckers have some nice finned breathers too.
Also some manifolds have the boss cast into the front where the early style manifolds had the breather tube hole, all you have to do is drill it out.

 

[gassersgarage]

Eventual slugge build up and blow=by without breathers.

 

[42chevy]

Definately run a PCV valve, you will regret it if you don't