I've seen a few really good threads about catch cans, and it looks like the consensus is that two separate cans is the best due to pressure variances and the fact that you don't want boost in places that shouldn't see any boost.

Here's my question: if the rocker breather and the PCV line both go into the intake anyway, why is having 1 catch can bad? The two lines are meeting up before the manifold, instead of at the manifold. They both ultimately converge with the intake air either way! Why do I need two catch cans?!

 

I don't think you need two. In fact, I don't think most people even need one.

 

under what sorts of applications / driving habits would a catch can be advisable?

 

i have one, just one, I've only seen most cars have one. You don't need one, but it's just one of those things, it keeps a lot of crap from going back into you intake and turbo. as you can see in my pic, i installed mine the subymod.com way, and you can see oil and crap in the intake line.

 

You mean you hooked it up to the crankcase only, not the PCV?

 

just the top, other people do it the other way, but I think that's overkill unless your ****.

 

I got both Breathers and crankcase going to the oil catch can and then to the intake inlet pipe, that seems like the only right way to me

 

http://forums.nasioc.com/forums/showthread.php?t=754710

-wdb