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@galognu Nice write up. Excellent location. Thank you for this. I went ahead and installed one on my 2009 GTS.
I chose the SPEEDWOW 300ml baffled catch can. great design, $35, filtered, dipstick, 5/8 fittings and comes with a nice bracket.
I modified the silver bracket the catch can came with, used the lower existing screw to mount on the top, I used a double sided 3M tape and the zip tie on the bottom to attached the bracket.
There is a perfect gap space to run the hoses behind and below the radiator hose to keep it away from the pulleys the radiator fan.
The dip stick is easily accessible. I will be emptying it every oil change from below. With 300ml capacity, hoping no need any sooner, nice to have a dipstick to be sure.
3/4 hoses barbed to 5/8, I used some 1 1/4 shrink tubing as suggested.
I bought a new URO Parts 94810724502 breather hose to source the Norma connectors.
- ended up putting the new one in and slicing off the connectors from the old one. https://www.rockauto.com/en/partsear...um=94810724502
I should have done this mod sooner, I am ready to get the valves walnut shell blasted. I will report back when time to emty.
Here is mine added. Very pleased. Thank you to all whom contributed to this thread.
So ive had my catch can setup for 6000 miles now. In the last 1000 miles Ive noticed a lot of oil consumption, so I started looking at the AOS diaphragm and my catch can. Diaphragm is fine, afterall i just replaced it when I did the catch can.
i have a 955 CTT and the can plumbed between three AOS and the 3 way valve (in place of the OE short elbo).
checked the can, had about 1 oz or so after 2000 miles, so its doing something.
I found a kot of oil in the 3 way valve, which with the catch can should have minimal to none.
started it and watch the Armormark 19/32 recommended hose on the 3 way valve side to the can collapse
Joefus, you talked a lot about this, as you had this issue. So is this bad or not?
Engine hasnt been smooth, kinda stumvling a bit assuming cause im burning so much oil. Tail pipes are nice an black too. Smoking after start up and warm too.
i changed the oil, checked the intercooler pipe which had nothing, bypassed the catch can and put the 90deg elbo back on from the AOS to the 3 way like stock, and all is good again.
So, I can only think the collapsing hose isn't a good thing
Maybe the Armormark 19/32 hose with heat cycling has just softened or weakend over time, now collapses easier?
so what hose should I use that doesn't collapse? I can add springs but would need like 3 ft to fill all the hose and don't want to reduce the flow too much either.
is the autohaux braided hose that many of you are using from amazon stiff enough to avoid collapsing? Is it emissions hose and can it hold up to oil, it looks to be fuel hose?
Petza, I see you used Porsche hose cause you mentioned it doesn't collapse. Can you give more details on that hose?
I did blow through the whole catch can setup, right into the hose I have exiting the AOS and while I could blow air through it, it wasn't super easy, like I obviously could through the short OE elbo. I could also suck through it and hear / feel the 3 way close a valve, just not super easy. I think the Armormark 19/32 hose, and perhaps my route between the engine and the air box is pinching flow a bit, in addition to the collspse at idle. Ill change the routing of the hose to just sit on top of the valve cover to avoid the pinching.
Last edited by Corvetteboy6988; 05-02-2024 at 12:24 AM.
Correct. This is exactly why I used the reinforced Porsche hose that they use for the brake booster connection on 928s. The Porsche part number is 999-181-022-51 and that gets you a couple feet of the 15/32" hose. Because it's smaller diameter is why I split it off into dual runs in and out of my AOS system, so my whole system including the AOS I chose was based on using this hose. It doesn't collapse under vaccum conditions and why Porsche uses it - if it did yiud lose the power assist on the braking system. Anywhere I needed a larger hose to get to the junctions of the reinforced hose I put springs inside the larger fuel line hose I used.
Based on my comments back in post #38 I think that at idle there is manifold vacuum, but the crankcase pressure is not yet enough to lift the AOS against the spring.
So the vacuum has nowhere to go and the AOS is not feeding it - the manifold pulls (sucks) against the 3 way valve - closing the side that goes down towards the turbos.
At some point in the RPM cycle before boost the crankcase pressure must be enough to lift the AOS and feed the vacuum in the inlet manifold. That's why we get oil in that can.
Once boost kicks in the manifold side of the 3 way valve closes and the crank case pressure goes down the other pipe towards the turbo intercooler.
I think Porsche chose hardened hoses with reinforcing ribs for these pipes for exactly this reason.
I bought 1 meter of 13.5mm dia and 1mm thickness stainless springs and put them inside the pipes and they no longer collapse. I couldn't get 14.5mm or 15mm dia springs in anything but 2mm thickness which were a little too stiff.
Yes, 3/4" for me. I wonder if they are just out of stock?
Oops, I see that only the 3/8” and 1/2” is rated for PCV use. Probably not the best option then. I wonder if using some easily-bendable hardline makes sense?
Im gonna get a bunch of springs, or go with a better hose. Thanks for the confirmation everyone.
BobcatBrian, so how do we know this Radium hose is any different than the Armormark 19/32 I used or non -collapsible like the Porsche hose Petza used?
I do like that its in 3/4:, it was a bear getting the 19/32" over the Norma connectors male ends. Plus it will keep the cross section wider if I do add springs (my concern about choking down the flow with springs in the 19/32 Armormark hose I currently have.
it would be nice if we could buy plastic ribbed hose similar to the stock hose, that is somewhat bendable (or can use heat to form). No collapse worries then. Although we would all be replacing them in 5-10 years like the OE ones!
Last edited by Corvetteboy6988; 05-03-2024 at 03:36 PM.
Im gonna get a bunch of springs, or go with a better hose. Thanks for the confirmation everyone.
BobcatBrian, so how do we know this Radium hose is any different than the Armormark 19/32 I used or non -collapsible like the Porsche hose Petza used?
I do like that its in 3/4:, it was a bear getting the 19/32" over the Norma connectors male ends. Plus it will keep the cross section wider if I do add springs (my concern about choking down the flow with springs in the 19/32 Armormark hose I currently have.
it would be nice if we could buy plastic ribbed hose similar to the stock hose, that is somewhat bendable (or can use heat to form). No collapse worries then. Although we would all be replacing them in 5-10 years like the OE ones!
All good points. I have not bought anything from Radium, but they make fancy schmancy catch cans. Maybe call/email them, ask about the intended use, mention that the Armormark hose you have collapses, and see what they say? Either way, good luck!
Email sent to Radium, Ill report back what they say.
I didnt notice this in the specs before, but it does state a vacuum rating, is that enough? Im assuming that how much it can handle without collapse. Anyway, I asked them.
3/4" PCV/Fuel Hose
Inside Diameter: 0.75" ID
Outside Diameter: 1.17" OD
Working Pressure: 305-psi
Burst Pressure: 1218-psi
Vacuum: 24-inHg
Last edited by Corvetteboy6988; 05-10-2024 at 03:31 PM.
Response from Radium, sounds good.
Im gonna order some of the 3/4" i think to easily fit over the stock size Normas, and to ensure good flow.
I want to get some hose braiding to slip over it for a more finished look, ill start looking
04-29-2024, 01:55 PM
2009 GTS
