remote breather set up?????

[61ragtop]

I have a rookie Question, I have noticed that some of your cars have AN lines going from the valve covers where the PCV and breathers would be. What is this and what is it for?

What are the benefits of what ever it is for a street car?

Are there kits for this? If not how are they made?

[Ron in SoCal]

Hey Rich - you're exactly right, it's a breather set up. Under high RPM's the motor builds up internal pressure and the oil wants to go somewhere, at best out the valve covers. By venting the valve covers w a breather set up, you give it a place to go - typically a catch can w a breather on top. It's debatable, but I've been told internal crankcase pressure also robs HP...

I've seen a number of kits and do it yourself set ups. I'd bet Summit has one. Here's Peterson's version:

http://www.amazon.com/Peterson-Syste.../dp/B003M8M4VU

[garickman]

Are these simply just cans that catch oil and let the engine breath? Or is there any type of baffles or filters in these cans?

[Van B]

I am pretty sure mine (Moroso) is just an empty can with a filter element on top. Any oil or condensation falls to the bottom. I put mine on because at high RPM it would spit oil all over the valve cover then run down onto the headers and generally make a mess.

[Flash68]

I was having the same problem recently until we put the Moroso baffles in my breathers. While I like a remote breather setup, I do like the valve covers that came with my car and was hoping to minimize unnecessary changes for cost reasons. So far the welded in baffles have stopped the excessive oil from spitting out.

[GregWeld]

In the old days -- cars just used a "road tube"...

The PCV is a "smog issue" where the fumes are recycled and burnt. There really isn't any vacuum created in the crankcase since the opposite valve cover has a filter/breather.

IF -- you run a vacuum pump -- you can get negative crankcase "pressure" and this helps with ring seal but that wasn't your question.

The easiest and best way to handle the crankcase pressure is if you can just use a PCV and breather... it's simple - it's clean - it's effective. But if you can't - then you can use breather/filters in both valve covers and just let the fumes vent to atmosphere. The only reason you'd go to a 'can' is when you're running the car hard and then the breather/filters load up with oil (as it condenses) and the oil starts dripping... Add some fan/wind - and it can blow these small drips all over the place.

The catch cans need to be drained... and the best way is to run the drain right back into the pan if possible so you never have to worry about it. If not that, then remember that you're going to drain the oil out the bottom and that can be messy too! So location becomes an issue.

Some times a guy will forget to drain the can -- and during an event, with running hard and hard cornering etc, a can placed over the top of the headers can blow oil and possibly start a fire at worst, and make a heck of mess at best.