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Engine Catch can

It's good to question everything. I'm not totally sure how this is possible either, hence why I was always under the impression the pcv valve was forced closed under boost (to avoid pressuring the valve cover). This is the service manual for the 2.0 T-GDI Theta II and the pages before/after the ones I previously provided show CAD of our engine bay/components including the turbo. Maybe Hyundai dropped the ball with the pcv diagram for this platform (which would be unfortunate). I am not 100% sure here, but it is the information provided by them for our engines. I see the pcv schematic table has a column for high load/acceleration but doesn't mention boost at all. As far as the vapors going through the breather tube , this scenario should happen when there is a high volume of blow-by (high load/acceleration). The built up blow-by should vent under its own pressure and with the help of a vacuum from the turbo (airbox/filter creates restriction leading to vacuum between airbox and turbo). So in this case the crankase would be venting ("breathing") all that excess blow-by coming from the cylinders. Under normal load/acceleration the fresh air coming from the breather is used to sweep the blow-by out of the system. Attached are the pages surrounding the pcv section showing CAD that matches our VN's
I have seen a few places in the service manuals where non-N vehicles are shown. Certainly I can see vacuum at the point where the breather attaches to the intake, but the blow by flow into the case permitting flow back up the breather completes the picture. Looking back it should have been pretty obvious...

Keep us posted on your catch can contents:)
 
I have seen a few places in the service manuals where non-N vehicles are shown. Certainly I can see vacuum at the point where the breather attaches to the intake, but the blow by flow into the case permitting flow back up the breather completes the picture. Looking back it should have been pretty obvious...

Keep us posted on your catch can contents:)
This is unfortunate . I will have to take the service manual with a grain of salt moving forward. & Most definately. Another measurement coming in 300 miles, oil lab results back next week , and most likely a baffled vent oil cap with a check ball coming.
 
That is correct. A gentleman on the other forum already has this setup installed. He suggests getting an O-ring to properly seal it up:

https://www.ebay.com/itm/Lot-of-10-1-1-2-O-D-3-16-C-S-70-Durometer-Nitrile-O-Ring-H-320/190548651350?ssPageName=STRK:MEBIDX:IT&_trksid=p2057872.m2749.l2649

You can find his install here:

https://www.velostern.com/forum/#/topics/745
UPDATE: The gentleman in the other forum has begun to experience problems with his breather application. The car is cutting power and creating flat spots with acceleration. Looks like the mod didn't work out:

https://www.velostern.com/forum/10-.../745-cfm-breather-w-checkball-2.html#post7259
 
Finished my 1st oil change last night. My God they were not lying when they said the drain plug is on there tight. My break-in oil also looked terrible and smelled terrible lmao. Make a long story short can collected 1 TBSP of pure oil. I could not visibly see any vapor at all that the Mishimoto can caught. This might change in the winter but I'm hoping the location of the can keeps it warm enough where not ALL vapor will condense in can. 1 TBSP of oil is roughly 15 ml. Oil was collected over the span of 1K miles. Mishimoto filter still looked good and clean so I did not service. Can still visibly had oil coated on all sides of walls. Mishimoto caught 20ml of crud in their can when running on the 1.6L Turbo Gamma Engine fitted to the 2019 Veloster Turbo. The article was posted in May but I do not know if that is when the test results were taken. Attached you will see pics of my collection and Mishimotos collection. Also attached you will see pics of can filter, empty can, break-in oil, and fresh Amsoil. 15ml that I caught is pretty close to the 20ml that Mishimoto caught. Our engines are "supposed" to be better in terms of blow-by I guess? Mishimoto can seems to be working as advertised. Money well spent. I do stop and go driving around town on the weekday but most of my commute is highway. On the weekend I also do stop and go driving in town but do travel from town to town usually every other week at a spirited speed :) Glad I finally got some data on this cans oil collection. It is a relatively a good can for the price with the micron filter. View attachment 8954 View attachment 8955 View attachment 8956 View attachment 8957 View attachment 8958 View attachment 8959 View attachment 8960
Finally got my oil analysis results back from Blackstone Labs and what do you know? Fuel dilution was <0.5%. So this means that with extremely minimal blow-by I was still able to capture a significant amount of oil (15ml) that is being vacuumed out of the valve cover. Next up is a 1000 mile catch can check after running Amsoil 0w-30 and possibly using a boroscope to peak at the turbo/valves etc. The first catch can results were with break-in oil so it will be interesting to see if the results change with a top of the line oil. Finally, the viscosity of the break-in oil was a tad thin for 0w-30. Makes me wonder what oil they actually put in the engine from factory. baby blue vn.JPG
 

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