[71SS454]

I've been doing alot of reading on PCV valves and evac systems. There are so many different theories, but with one common theme, you must evac the crankcase. Now I know that running just two breathers is wrong. Been there, done that, got the oily t-shirt to prove it. But what I'm wondering is should I just run a PCV in the intake with breathers in the valve covers, or should I just run an exhaust evac system, or should I run both. And if I run the pan evac system, I don't run the open breathers anywhere correct?

This is so much simplier when it's a cut and dry street or race car. Street = pcv, oil fill cap, and valve cover breather into air cleaner base. Strip = vacuum pump, oil seperator tank. Street/strip = ????????

Thanks.

 

[chevyIIheavy]

run a e vac system..... it works better :yes:

you can sorta see it .... i run a pan e vac on the street and it works fine no problems and no oil leaks

 

[chevyIIheavy]

if you want to run a vacume pump thats ok too but very expensive but its the best crackcase evac system :yes: if your on a budget i would go with the pan e vac

 

[71SS454]

No, this isn't a vacuum pump engine. I was just stating the differences between the different applications.

 

[chevyIIheavy]

oh sorry i misunderstood your thread yeah i would run an pan e vac then you wont contaminate your intake charge with oil from blowbye :yes:

 

[The Big Al]

If you don't have a high rpm application just use the PCV system.


You click on the pic to make larger, you can also click again on icon on lower left after first Click!

Use the closed manifold system. (You can just run a breather at valve cover)

 

[71SS454]

I guess I should of aded that. It's reving around 3400rpm on the higway, but I'll shift at 6800 and turn 7200 thru the lights at the track (that's what we're figuring it should be, will know definately after the dyno). So I guess that would be considered a high rpm engine?

 

[The Big Al]

Go to this link!

Al

http://www.stevesnovasite.com/forums/showthread.php?t=76896&highlight=ventilation

 

[71SS454]

I read that one last night. Then I read this one:
http://www.stevesnovasite.com/forums/showthread.php?t=116605
So , running the pan-evac system, is it better to run it as a closed system as in the original thread, or to use the breathers as well as in the newer thread?Does adding the breathers make much of a difference?

The other idea was to run breathers in the valve covers, and install a PCV valve in the intake manifold valley tray, but run it thru an oil-water seperator/catch can before the intake so as to not suck all that into the engine.

But I also like your original idea of running the pan-evac in the valve covers, and ther PCV in the intake to help at low exhaust speeds (lower rpm).

That's what I like about this site, there's alot of great information here, and many ways to acheive a similar goal, it's just deciding which one is right for a given application.

 

[6NOVA4]

there should be no reason to run a separator tank. If your getting water in the crankcase its because your not warming up the engine enough and running short trips or you got a water leak somewhere. All my street and street/strip engines use a PCV and a breather or 2 open breathers with excellent results. On my race engines I use Pan-evacs and no breathers, or if the budget allows a vacuum pump.

 

[71SS454]

The seperator tank is so that the engine dosen't suck in the slight oil mist and condensation thru the PCV valve. I can't find the thread on it or I would post it for you. You'd eb surprised at what a pcv valve will suck into your engine, especially at high rpm's.