davenew

This is what prompted me to buy a new spider hose and get busy on a catch can. This area is getting nasty, not to mention my driver's side IC hose having oil in it.
<img src="http://dave-new.com/S4/spider_hose/cut_new_hose/DSCN0511.JPG">

I very carefully cut the hose between the two fittings of the new spider hose.
<img src="http://dave-new.com/S4/spider_hose/cut_new_hose/DSCN0504.JPG">

<img src="http://dave-new.com/S4/spider_hose/cut_new_hose/DSCN0509.JPG">

I decided to cut this plastic hose because it needs to be removed to run hoses to and from a catch can.
<img src="http://dave-new.com/S4/spider_hose/cut_new_hose/DSCN0510.JPG">

I'll also remove the smaller long plastic hose on the other side (the one that goes to F hose) and plug that port. Of course, I'll also plug the F hose and remove that check valve.
<img src="http://dave-new.com/S4/spider_hose/MVC-791X.JPG">

Here's the plan. To draw fumes out of the engine: Connect a hose to the large port on the spider cylinder. Run that hose to the catch can.

To get from the can (located behind the firewall) back to the engine: Run a large hose from the can, to a Tee. One hose will run to the limiting valve at the Y-pipe. The other smaller hose will run from the Tee, to the relocated F-hose check valve, then into another tee in the brake hose shown in the picture below. Do you think this will reduce vacuum to the brake master cylinder?
<img src="http://dave-new.com/S4/spider_hose/cut_new_hose/DSCN0514.JPG">

This is pretty much what everyone else is doing. I'll try making a PVC pipe catch can before spending $150+ like the high rollers. It will look bad but at least it'll be hidden behind the firewall. The limiting valve port is 0.064" dia, and the barbs are 0.0723" dia. My only problem will be routing two 3/4" ID hoses into the firewall.

I'd like to thank everyone else who posted pics of their catch can setups! The larger pics are for the older guys

davenew

BTW, does anyone believe the F-hose sucks up as much oil as the Y-pipe?

DAP@EPL

The F-hose sucks oil when the manifold is under vacuum. The Y-pipe takes it in when you are under boost. When are you worried about not consuming oil vapors?

-Dave Pramanik

DxC

um, whats the purpose of installing a catch can?

davenew

Take a look at the link. Only '00 S4s seem to have the problem of excessive oil in the inlet pipes.<ul><li><a href="http://www.accmachtech.com/pcvcatchcans.htm">http://www.accmachtech.com/pcvcatchcans.htm</a></li></ul>

Captain Matt, I be

id just disconnect and cap off the manifold connection

davenew

The PVC system was designed for stock airflow. The Y-pipe PVC connection port creates vacuum proportional to the velocity of the intake airflow, right? With higher stage 3 airflow, I assume the Y-pipe connection is creating more vacuum than stock, which might explain why so much oil gets sucked into the Y-pipe.

The F-hose port sucks in PVC fumes based on intake manifold vacuum. That's the same regardless of stock or stage 3.

That's why I believe most of the oil is coming in through the Y-pipe connection. Then again, I'm just guessing. I'll block off the F-hose port so I don't have to waste more time thinking about it.