I have seen many newer montes with a breather filter in place of their oil cap. In consideration of doing this to my own car, what are the gains, pros, cons, and the prerequisites to this?

 

from an earlier post by chibi Mike....

 

What does the oil filler cap have to do with the intercooler? I have no clue. I know that my "old" pcv system vents to atmosphere, but I don't know why... I am really curious. I'm not posting this to be contrary.

 

Greg, just something I remember reading here....I'm also not trying to be contrary either....

 

If you need to have a vent for your crankcase because you had to disable your PCV system, then you should run the filter oil cap.

If you want to have it, just because you think it looks cool but still have a functioning PCV system, then you aren't helping.

 

thissssss

 

And this is why I posted on this subject. I didn't know if it would help or strictly for show.

How would running an intercooler be any different on whether its needed or not

 

Because you have to disable the PCV system in your engine in order to run one most of the time.

 

It doesn't. A breather would usually take the place of the oil filler cap, as it allows a direct vent to the crankcase in a car that doesn't have a working pcv system.

For the OP, there is no benefit to this unless you're going turbo (in which case the benefit is the turbo lol, and there just isn't a way around the breather otherwise), and on a stock n/a car could end up making your car run worse (you'd be creating a vacuum leak essentially).

Not really. Of the three vendors that are currently selling L67/L32 intercoolers, the ZZP and PRJ have full stock pcv function. The W-body store core doesn't retain full pcv function, but it does retain the vacuum source from the rear head. It only blocks off the fresh air source going into the front head. I guess a few of the older cores had a setup similar to the WBS core, but I wouldn't say most.
Also for an intercooler core that blocks off the front stock pcv passages (like the WBS one), you're better off routing metered air into the valve cover instead of running a breather. I guess this can be a little tricky with a stock L67 throttlebody, but is really easy with a northstar or LS1 throttlebody setup.

 

Thanks biggriggs. Great info.