No can. no matter what the internal design is will work unless it nears 1 qt of internal volume to allow the speed of the flow, or velocity to slow enough to prevent the Bernoulli effect from pulling much of the liquid through.
Here is a good read:
There is always debate about catchcans and effectiveness. We, for several years have had a challenge out to any brand catach-can to demonstrate there is no equal to the effectiveness of the RX system, and get plenty of flak from some on this. Our challenge has been, and continues to be as follows:
Install the RX can inline AFTER any other can, no matter the brand or model, especially the popular ones like Moroso, Billet prototypes (any of the dozens branded different but the same design) JLT, etc. and the RX can will catch as much or more, than any of these other "Placebo" cans. All cans catch oil, that is not in debate. What is the concern is if your only trapping a small amount, and most of the oil most is still traveling right through any can and still being ingested into your intake air charge, your not correcting the issues related to oil ingestion. So, since we have done the tests ourselves on dozens of popular cans, it is hard for a consumer to see this as accurate and unbiased (the Elite E2 has turned out to be a close second and performs excellent) we have extended this challenge to anyone that will demonstrate they will do an unbiased test for 1000-2000 miles and document all in detail starting with both cleaned and oil free, and also at the end of the test are free to do it in reverse order (RX first, any can after) and I stress again, un-biased with no relationship with any of the vendors, post up the results in an accurate manor. We are looking for some here as well to do this on the CTS-V, and any other model/engine.
This is to wade through the hype and BS.....this is an open challenge ongoing.
Here is the most recent result:
I've had a UPR catch can on my 5.0 since last summer. It catches a lot, especially in the cold months. But I'll get right to my test. I added an RX can inline after my UPR can to see if the UPR was missing anything. And if it was allowing some to pass through, was it enough for the RX to catch anything? I don't drive a lot of miles regularly since my F150 is not a daily driver, so my results will take some time. This thread is to document how I set it up and what I catch over time.
I installed the RX can just as the directions explained, but I routed the hoses differently. I left my UPR can right where it's been for months, but rerouted one hose. I left the hose from the passenger side of the engine to the inlet of the UPR can. Then a new hose from UPR can outlet, routed to the inlet of the RX can. The RX outlet hose goes back to the engine. The PCV exhaust now flows from the engine, through the UPR, then through the RX, and finally back up to the engine intake.
Before installing everything for the test, I cleaned the UPR can thoroughly. The bottom of the can (inside) was covered with a thin layer of stiff sludge that I could only clean out using gas. I'm glad that was caught, along with the ounces of oil, water, etc, over the months I've been emptying it. But I was surprised at the outlet hose from the UPR can. It was wet with oil. Obviously some was getting through the can and back to my intake. I've never let the can get close to half full before emptying it. Nearly every time I've emptied it, there was 1/4" or less in the bottom. I'm noting this in case someone thinks I left the UPR get overfilled and it flowed through. Nevertheless, I started this test after cleaning everything for a fresh start.
I plan to leave this setup on for a thousand miles or so, and report my findings from each can.
1st picture: UPR can as it was originally installed.
2nd: CleanUPR can.
3rd: RX can installed. The hose in the top center of the can is the inlet. The outlet hose on the right has a check valve.
4th: Engine outlet to UPR inlet on left of can. UPR outlet on right side of can routed around (smaller hose) to the RX inlet. You can also see the other smaller hose coming back up from the RX can and ending at the intake on the engine.
And the 1000 mile result:
1000 Miles of Testing Results
- The Weather has been warmer lately. So the test began with sub freezing temperatures, and gradually increased through the 70's and topped off in the mid 80's yesterday. I couldn't have asked for a better range of temperatures for this test.
- What they caught was astounding to me. UPR was first in line, with the RX after it to catch anything the UPR might miss.
The UPR stayed on track with what it has been accumulating for many months. Each time I emptied them, it had about the same amount. It's contents were mostly oil which smelled like used oil. It caught 17cc total which is just under 3 1/2 tsp.
The RX had more than the UPR each time I emptied them. It's contents were an oil/fuel/water type mix that had a much stronger odor. Not a fuel smell, but a sharper chemical smell compared to the odor of used oil. It caught a total of 67cc which is just over 13 1/2 tsp.
- Final totals:
UPR - 17cc
RX - 67cc
So, who has a Moroso or other can installed that is willing to do a completely unbiased test...let us know.
