MikeD-9000

Ok Lem, Any ideas on how to best get that vacuum on the PCV? My understanding is that on most vehicles when you put a catch in direct replacement to the PCV valve, you cap off the intake inlet, and vent the PCVs outlet to atmosphere. If the spider hose and F hose are interconnected, then one of the hoses is where a vacuum is coming from, and that needs a one way valve to prevent that from being a vacuum leak.

I don't at all understand why I would want a vacuum on the intake side. At extremes, the intake plumbing before the mass air is so wide open, that you would almost never have ANY vacuum applied to the PCV. This irregular vacuum , if it even exists, wouldn't do much for venting crankcase gases. At least not much more than simply allowing them to escape.

If I understood which of these mystery hoses were strictly crankcase vents, i'd catch can those, and cap off the vacuumed one.

lemieux@curbside

where you do not run the possibility of a boost leak like you would if it's connected to intake manifold. run the shortest possible hoses and keep the stock diameter to help getting rid of the crankcase pressure from blowby. you want the catch can to retain the blowby OIL more than anything. it would be nice to use an electric vacuum pump but it's not worth it. ideal would be route the oil catch can back to the oilpan / valley pan so you don't have to empty the damn thing and when the engine is at rest the oil goes back where it belongs - in the oil pan and i't not all over your intake tract and esp in the driver side IC. i always have a 1/2 cup of oil sitting there LOL.
when i put my newly rebuilt engine in i'll also place a catch-can using most of the stock piping. the best spot is on the firewall behind the engine i think, or behind the firewall near the battery , but i'd like to keep that warm in the winter so water vapors do not freeze , and if they do it will not last .
my 1/2 cent.

Paracaidista2.7T

to the catch can and from the catch can to the distributor piece on the spider hose. Seems to work, should I change it?

lemieux@curbside

you want that catch can retaining the oil and vapors coming from ALL 3 points : 2 valve covers and 1 valley cover.. before being pulled into the intake (Y pipe as you'd probably cap the intake mani connection - i did)

Paracaidista2.7T

Wilco, thanks. That was bugging me, but I wanted confirmation.