2.0T dual catch can configuration

hummus

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Hi all. I decided to try out dual catch cans on my 2.0T. I wanted to see if they would be effective for me. I have no experience with this, but have been researching, studying, and planning for some time. My objectives are:

(1) Retain the car's ability to relieve positive crankcase pressure as designed, which meant no plumbing redirection, minimizing bends, and retaining stock hose diameters where possible. If I even suspect this is compromised, I go back to stock
(2) Mount low: position the CC inlets downhill from the breather and PCV as much as possible
(3) Mount cold: position the CC canisters away from heat sources as much as possible while keeping hose runs reasonably short and direct
(4) Avoid permanent changes such as drilling

I used generic replicas of the Mishimoto compact, complete with what appears to be identical baffling and brass filter on the outlet. Build quality feels excellent in hand, with good material heft and clean machining/tapping. Both are 3-port, 2 in/1 out designs, and I simply plugged one inlet on each using the 3/8" NPT plug on the bottom, an am using them as 2 port units. Other supplies:
  • 3/8" ID, 1/2" ID, and 5/8" ID fuel line (which I haven't used yet)
  • brass 3/8" hose barbs (OCCs have 3/8" NPT thread and come with 1/2" ID barbs)
  • brass 3/8" and 1/2" union
  • drain plugs (one EZ filter and one generic)
  • sealant tape, corner braces to use as brackets, assorted bolts, screws, nuts, washers, etc.
  • titanium drill bits to modify corner braces
  • 3/8" check valve for the return to intake manifold line (not installed yet)
OCCs were $30 each and I spent at least that much on accessories, mostly due to lack of patience finding suitable fuel line (which lead to buying more than I needed) and exorbitant shipping cost on the check valve.

Pictures show how I mounted both sides. I'm trying out the current plumbing for now, and will probably re-route the outlet on the breather side with a regular 5/8 hose.

PCV side
20t pcv occ.webp

For the PCV side, I used what appears to be a mounting point for the 3.3T driver side air filter housing with a 3-4" corner brace. I installed a new 3/8" fuel line from the PCV to the inlet on the OCC, and used a brass union to connect more 3/8" line to the existing line on the intake manifold return, which opens to 1/2" at the manifold. I got lucky with this location because in addition to being away from heat sources, the inlet hose touches what appears to be a refrigerant line. Not sure if that actually helps, but the open can picture shows what this OCC caught in 180 miles!
20t pcv occ caught.webp
I haven't noticed any issues running without a check valve on the return to intake manifold so far, but still plan to try one to replace the brass union leading into the manifold.

Breather/turbo side
20t turbo occ.webp

For the breather side, I used an existing threaded stud (m10 if I recall correctly) along the passenger side of the engine compartment with two smaller corner braces in a swiveling configuration. I removed the double-corner joint after the right angle hose coming out of the breather port, ran fresh 1/2" line from there to the inlet on the OCC, and then more 1/2" from the outlet into the remaining stock line which opens to 5/8" at the intake tube. In the picture, it looks like the bendy line returning to intake tract might be touching the exhaust manifold shield thing, but it's actually got more than 2" of clearance--which is actually not much different from stock. If I keep everything installed, I will probably still replace this with a 5/8" run from the OCC to the intake.

So far, no negative effects in terms of running or error messages. I have been getting better mpg than before, but that's probably because I have concentrated more on light throttle to keep boosting down until I install the check valve. I am really surprised at how much the PCV can caught in about a week of driving though. I am looking forward to checking the breather side, and the cleanliness of both outlets to see how much blow-by the cans are letting through.

On my objectives, I believe I accomplished mounting low and no drilling, did okay on mounting cold, and I'm feeling pretty good about the crank case still evacuating effectively. But, the whole thing is still on trial and may come right back out. I'll report back after some more miles. Let me know if any questions, and please share any insight.

Thanks and sorry about the long post.
 
Received and installed the check valve today: Kynar unit that seems to be popular with GNX and Evo drivers. Took the opportunity to inspect the manifold return line after 300 miles. Looks quite dry to me, especially considering how much that can caught after just 180 miles. Cleaned up the routing a little bit, replaced the engine cover will now run the car for a while and see what happens.

dualfinished1.webp
dualfinished2.webp
 
Hi, i'm planning on installing a catch can on my 2.0 too but only on the pcv side.
Could you tell me if the catch can on the breather side catched a lot of oil?(wanna know if i need a second one) And is it possible to show a picture of where you connected the occ on the pcv side?
 
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Keep in mind that I'm also new to the catch can thing, so take my words with a grain of salt. I probably spent 20 hours reading and re-reading posts and articles, as well as watching and re-watching instructional videos. I also probably studied under my hood for a total of 2 hours or so to look for mounting spots and deduce where the plumbing should go. That doesn't make me an expert though--just careful, which I what I would recommend for anyone.

It's too soon for me to tell how much the breather side will catch; it's only a bit over 100 miles so far. I wouldn't be surprised if it doesn't catch as much as the pcv side, because (1) I don't drive very aggressively so I don't go into boost much and (2) my mounting location for the breather side does not have the advantage of being as low as the pcv side can, which is also running the inlet hose right up against a cold refrigerant pipe.

However, I didn't install the second can because of how much it will catch, but rather based on my understanding of when it catches it, and where the residue ends up if not caught.
  • When: the car is running hard in boost, exactly when you don't want pre-detonation due to contaminated fuel mixture theoretically reducing effective octane
  • Where: upstream of the turbo and intercooler. I have seen modern turbo cars with gobs of oil in the intercooler plumbing and am working to avoid that for my beloved Stinger
Here is a picture of the hose I intercepted with the pcv side can. It's the one with the foam sleeve around it, starting a few inches to the right of the oil cap in this picture (in terms of the car, it's straight back from the oil cap).

pcv intercept.webp

To the best of my knowledge, the higher up port on the cylinder head is the PCV. I detached the factory hose from there and ran fresh 3/8" fuel line from there to the inlet on the catch can. In the picture on my first post, this is the line that has that same foam sleeve, but I moved it shield my line from what appears to be a coolant line (actually this might be charged air from the turbo--again, I'm not expert).

The other end goes in to the intake manifold. I decided to leave that hose in place; it is 1/2" where it goes into the manifold. In order to avoid a severe angle or kink, i spun that hose on the manifold barb so that the loose end pointed toward the front of the car, and then coupled it with a 3/8" check valve to more 3/8" fuel line, then to the outlet port on the catch can. In my first post, this is the line that is closer to the camera.

The best recommendation I can give you is to research, research, research, and ask an experienced friend if you can. Also be extremely careful moving or removing any factory hoses. The barbs on the PCV, intake manifold, breather...basically all of them are plastic and I'm not sure how sturdy they are. Stay safe and enjoy. Let me know if any other questions.
 
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Following up about 3,000 miles later, here is what my cans caught. Add maybe 10-15% more for residue that I wiped off the cans, baffles, etc. each time I emptied them. The cheapo cans themselves never failed, though the piece directing the air to "swirl" upon entering the can was evidently rattle-can painted and started to peel. The rest of the surfaces held up fine, and the outlet hoses remained impressively dry.

I would say the cans worked as advertised. Anyone's guess as to how beneficial it was to have them though. If you look closely at the picture, they seemed to catch more fuel (or fuelly water) than oil, though I was glad the pudding mess in the PCV side can didn't go back into the intake.

caught.webp
 
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HI hummus thank you very much for good illustration of the cc connections for stinger 2.0T. Looks like you discard the short L shape original hose for cc connection on pcv side ,but the picture isn't too clear from that angle. can you please upload a picture from cc side to make sure hows pcv side was done. it will be much appriciated.
 
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