What did you do to your FL5 today?

[SpoolinFK8]

I am very curious why you chose the AOS over the dual catch cans?

I just purchased the dual catch can kit, but have not yet installed it.

based on my limited understanding, the dual catch can is "better"?

I have always ran single AOS’s on all my cars no issue’s for street use. Never had any issues with running just one. In general single AOS would require more frequent check of oil buildups in the can, where in the case of a dual system the second can acting as a backup if the first one fills up. This implying you’re tracking or pushing your engine hard all the time. For street use and short light sprints a Single AOS works fine. I had it on the fk8, and for me to reach 2-3mm of oil buildups it took roughly over a year. The Radium at least has a dip stick which make checking a whole lot easier.

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[Two Step Performance]

I am very curious why you chose the AOS over the dual catch cans?

I just purchased the dual catch can kit, but have not yet installed it.

based on my limited understanding, the dual catch can is "better"?

Watch out for smoke from the exhaust after installing the dual Radium kit. We've had a couple of customers report it.

 

[SpoolinFK8]

It's no longer CW for the next few years! Got it wrapped with KPMF Blue Black Iridescent, and the final outcome is even better than I imagined!

Love the shift from a very vibrant blue, to purple, then navy blue, and even black, depending on the lighting at the time. When the car was revealed to me the side marker was still orange, and I requested if that could be wrapped as well. The guys did it on the spot, and it's so much cleaner!

Over the winter the car will receive tint, caliper color change, wheel swap to something else in Silver and likely 19's, maybe a lip (still can't decide on one), and my next post will showcase the APR Diffuser that we just installed as well.

Reminds me of the R34 GTR paint scheme.

 

[SpoolinFK8]

Watch out for smoke from the exhaust after installing the dual Radium kit. We've had a couple of customers report it.

Read a few reviews about that as well with the dual, and even one with the Single. Sounds to me like a faulty batch or user install error.

 

[zumbooruk]

I have always ran single AOS’s on all my cars no issue’s for street use. Never had any issues with running just one. In general single AOS would require more frequent check of oil buildups in the can, where in the case of a dual system the second can acting as a backup if the first one fills up. This implying you’re tracking or pushing your engine hard all the time. For street use and short light sprints a Single AOS works fine. I had it on the fk8, and for me to reach 2-3mm of oil buildups it took roughly over a year. The Radium at least has a dip stick which make checking a whole lot easier.

my limited research shows that they work differently. the AOS cycles oil back to the oil pan where as the catch can keeps the oil in the can (and has to be checked and emptied)

the AOS only attaches to the PCV, whereas with the dual catch cans, one attaches to the PCV and the other to the CCV (i.e. not an overflow backup).


out of curiosity, I've asked my favorite AI tool, Grok:

The Radium Engineering Air-Oil Separator (AOS, specifically their AOS-R model) and dual catch cans are both crankcase ventilation solutions designed to capture blow-by gases, oil vapors, water, and unburnt fuel from the PCV (positive crankcase ventilation) and CCV (crankcase ventilation) systems in turbocharged engines like the K20C1 in your 11th-gen Civic Type R (FL5).

This prevents contaminants from entering the intake manifold, intercooler, or turbo, which can cause carbon buildup, reduced efficiency, detonation, or oily residue over time.

That said, they're not identical products. The dual catch cans are more of a "collection" system, while the AOS is a "recirculation" system. I'll break down the key differences below:

Aspect	Radium AOS (AOS-R)	Radium Dual Catch Cans
Core Function	Separates oil/vapors from gases, then automatically returns clean oil to the crankcase (via a drain line to the oil pan or block). Gases are routed back to the intake. Includes a heated base (plumbed to engine coolant) to evaporate water and prevent sludge buildup.	Two separate cans (one for PCV side, one for CCV side) collect oil, water, and vapors in sealed reservoirs. Gases pass through cleaned and return to the intake, but liquids stay trapped until you drain them. Uses baffling and stainless media for separation.
Maintenance	Low: Oil recirculates automatically, so no regular draining needed. Check/clean the stainless media occasionally (every oil change, ~5-7k miles for your driving). In hot CA weather, the heating helps with moisture from blow-by.	Higher: Drain the cans every 1-3k miles (more often with aggressive driving, as PCV side fills faster under boost). Each can has a dipstick and bottom drain petcock—simple DIY, but forget it and you risk overfill/backflow. Fluid Lock tech prevents air blockage if overfilled.
Capacity & Design	Single unit, compact (fits in engine bay near firewall or battery). Larger internal volume for high blow-by; heated plate focuses on oil return.	Dual units for targeted capture (PCV for boost/load conditions, CCV for idle/low-load). Each ~0.5-1qt capacity; modular for easier placement in the FL5's tight bay (e.g., PCV near turbo, CCV near valve cover).
Performance Impact	Better for longevity—maintains consistent oil levels without gradual loss (no "topping off" needed). Reduces crankcase pressure buildup; ideal for hot climates as heating manages water vapor. Minimal restriction under WOT.	Excellent at capturing contaminants during spirited runs (PCV can catches more under boost). Prevents oil dilution in intake but requires monitoring to avoid issues. Slight edge in raw separation for modified setups.
Installation on FL5	Inline on PCV line; requires tapping the oil pan/block for return drain (intermediate DIY: drill/tap with engine out or use adapters). Hoses/fittings included; ~2-4 hours. Compatible with stock or mild mods.	Bolt-on to PCV and CCV lines with brackets/hoses; no pan tapping. FL5-specific kit (same as FK8) fits LHD models; ~1-3 hours DIY. Often installed together for full coverage.
Pros for Your Use Case	Hands-off operation suits "keep it forever" mindset—less risk of forgetting maintenance. Heat management is a win in 115°F+ SoCal summers (less condensation). Emissions-safe closed loop.	More effective at full capture during enthusiastic driving (e.g., canyon runs), protecting valves/turbo long-term. Affordable entry (~$300-400 for dual kit) and proven on FL5s.
Cons for Your Use Case	Slightly more invasive install; if not heated properly, could have minor water issues (rare). Not as "set it and forget it" if you add big mods later.	Requires periodic draining (track fluid color for engine health clues). In extreme heat, more water collection means more frequent checks.
Cost (Approx.)	$400-500 (kit with heaters/hoses).	$350-450 (dual kit; add $50 for remote drain if you want easier access).

I'd lean toward the dual catch cans if you're okay with the minor maintenance, they're battle-tested on FK8/FL5 Type Rs, capture more aggressively under boost, and are easier to install without modifying the oil pan. Emptying them becomes a quick habit, like checking tire pressure, and it lets you monitor blow-by for early wear signs (e.g., excessive oil could indicate ring issues).

If you hate maintenance and want true set-it-and-forget-it, go AOS, it's better for oil preservation.

If you're modding further (e.g., intake or downpipe), the dual cans scale better.

 

[Two Step Performance]

Read a few reviews about that as well with the dual, and even one with the Single. Sounds to me like a faulty batch or user install error.

We tried to consult with Radium on this after seeing it multiple times and they would not entertain the possibility of a product issue of any kind so for now we recommend staying away from them.

 

[zumbooruk]

We tried to consult with Radium on this after seeing it multiple times and they would not entertain the possibility of a product issue of any kind so for now we recommend staying away from them.

Thanks you.

Should I install my dual catch cans?

If so, what to watch out for during installation to avoid the smoke issue?

 

[Two Step Performance]

Thanks you.

Should I install my dual catch cans?

If so, what to watch out for during installation to avoid the smoke issue?

I would not recommend it. There is very little upside and a notable (potential) downside.

 

[SpoolinFK8]

my limited research shows that they work differently. the AOS cycles oil back to the oil pan where as the catch can keeps the oil in the can (and has to be checked and emptied)

the AOS only attaches to the PCV, whereas with the dual catch cans, one attaches to the PCV and the other to the CCV (i.e. not an overflow backup).


out of curiosity, I've asked my favorite AI tool, Grok:

The Radium Engineering Air-Oil Separator (AOS, specifically their AOS-R model) and dual catch cans are both crankcase ventilation solutions designed to capture blow-by gases, oil vapors, water, and unburnt fuel from the PCV (positive crankcase ventilation) and CCV (crankcase ventilation) systems in turbocharged engines like the K20C1 in your 11th-gen Civic Type R (FL5).

This prevents contaminants from entering the intake manifold, intercooler, or turbo, which can cause carbon buildup, reduced efficiency, detonation, or oily residue over time.

That said, they're not identical products. The dual catch cans are more of a "collection" system, while the AOS is a "recirculation" system. I'll break down the key differences below:

Aspect	Radium AOS (AOS-R)	Radium Dual Catch Cans
Core Function	Separates oil/vapors from gases, then automatically returns clean oil to the crankcase (via a drain line to the oil pan or block). Gases are routed back to the intake. Includes a heated base (plumbed to engine coolant) to evaporate water and prevent sludge buildup.	Two separate cans (one for PCV side, one for CCV side) collect oil, water, and vapors in sealed reservoirs. Gases pass through cleaned and return to the intake, but liquids stay trapped until you drain them. Uses baffling and stainless media for separation.
Maintenance	Low: Oil recirculates automatically, so no regular draining needed. Check/clean the stainless media occasionally (every oil change, ~5-7k miles for your driving). In hot CA weather, the heating helps with moisture from blow-by.	Higher: Drain the cans every 1-3k miles (more often with aggressive driving, as PCV side fills faster under boost). Each can has a dipstick and bottom drain petcock—simple DIY, but forget it and you risk overfill/backflow. Fluid Lock tech prevents air blockage if overfilled.
Capacity & Design	Single unit, compact (fits in engine bay near firewall or battery). Larger internal volume for high blow-by; heated plate focuses on oil return.	Dual units for targeted capture (PCV for boost/load conditions, CCV for idle/low-load). Each ~0.5-1qt capacity; modular for easier placement in the FL5's tight bay (e.g., PCV near turbo, CCV near valve cover).
Performance Impact	Better for longevity—maintains consistent oil levels without gradual loss (no "topping off" needed). Reduces crankcase pressure buildup; ideal for hot climates as heating manages water vapor. Minimal restriction under WOT.	Excellent at capturing contaminants during spirited runs (PCV can catches more under boost). Prevents oil dilution in intake but requires monitoring to avoid issues. Slight edge in raw separation for modified setups.
Installation on FL5	Inline on PCV line; requires tapping the oil pan/block for return drain (intermediate DIY: drill/tap with engine out or use adapters). Hoses/fittings included; ~2-4 hours. Compatible with stock or mild mods.	Bolt-on to PCV and CCV lines with brackets/hoses; no pan tapping. FL5-specific kit (same as FK8) fits LHD models; ~1-3 hours DIY. Often installed together for full coverage.
Pros for Your Use Case	Hands-off operation suits "keep it forever" mindset—less risk of forgetting maintenance. Heat management is a win in 115°F+ SoCal summers (less condensation). Emissions-safe closed loop.	More effective at full capture during enthusiastic driving (e.g., canyon runs), protecting valves/turbo long-term. Affordable entry (~$300-400 for dual kit) and proven on FL5s.
Cons for Your Use Case	Slightly more invasive install; if not heated properly, could have minor water issues (rare). Not as "set it and forget it" if you add big mods later.	Requires periodic draining (track fluid color for engine health clues). In extreme heat, more water collection means more frequent checks.
Cost (Approx.)	$400-500 (kit with heaters/hoses).	$350-450 (dual kit; add $50 for remote drain if you want easier access).

I'd lean toward the dual catch cans if you're okay with the minor maintenance, they're battle-tested on FK8/FL5 Type Rs, capture more aggressively under boost, and are easier to install without modifying the oil pan. Emptying them becomes a quick habit, like checking tire pressure, and it lets you monitor blow-by for early wear signs (e.g., excessive oil could indicate ring issues).

If you hate maintenance and want true set-it-and-forget-it, go AOS, it's better for oil preservation.

If you're modding further (e.g., intake or downpipe), the dual cans scale better.

I believe there’s some confusion about the products you and I are referring to, and you asking an AI for information rather than going to their site and doing the search yourself , the unit that i have and installed is a simple and basic oil catch-can. it does is take the PVC line that goes from the valve head cover down to the intake manifold and adds a catch-can to help stop unwanted positive crankcase vapor, unused fuel, and oil sludge back into the intake manifold. Hence why they say install and forget. The other two systems that Radium makes the single CCV kit goes inline with the crankcase line and mounts next to the engine mount. And the one you have, the dual kit is just a combination of both the PVC and CCV kit,

 

[zumbooruk]

I believe there’s some confusion about the products you and I are referring to, and you asking an AI for information rather than going to their site and doing the search yourself , the unit that i have and installed is a simple and basic oil catch-can. it does is take the PVC line that goes from the valve head cover down to the intake manifold and adds a catch-can to help stop unwanted positive crankcase vapor, unused fuel, and oil sludge back into the intake manifold. Hence why they say install and forget. The other two systems that Radium makes the single CCV kit goes inline with the crankcase line and mounts next to the engine mount. And the one you have, the dual kit is just a combination of both the PVC and CCV kit,

Definitely some confusion. sorry.

There are four different Radium products. AOS-R, PCV, CCV, and the dual PCV/CCV

However, the AOS-R is not made for the FL5, probably since the K20C1 has a built-in Air Oil Separator, i.e. the AOS-R is indeed not needed for the K20C1

Yet you mentioned AOS, which is what got me so very confused. sorry.

Which Radium part did you install?

The smoke issue seems to be from the Radium CCV catch can, where crankcase pressure goes positive causing oil to get past the seals into the hot side, burns on the turbine, and exits as smoke, especially noticeable on decel or idle after a hard pull.

I just found out that some other brands of CCV catch cans have larger hoses which minimize the pressure.

So even though I purchased the Radium dual PCV/CCV catch cans, I might only install the PCV side. or maybe just sell the kit (though probably no one would want it...)


I indeed know very little about engines (I am a software guy...) and I am well aware of AI's limitations, and I always double check the actual sources.

 

[SpoolinFK8]

Definitely some confusion. sorry.

There are four different Radium products. AOS-R, PCV, CCV, and the dual PCV/CCV

However, the AOS-R is not made for the FL5, probably since the K20C1 has a built-in Air Oil Separator, i.e. the AOS-R is indeed not needed for the K20C1

Yet you mentioned AOS, which is what got me so very confused. sorry.

Which Radium part did you install?

The smoke issue seems to be from the Radium CCV catch can, where crankcase pressure goes positive causing oil to get past the seals into the hot side, burns on the turbine, and exits as smoke, especially noticeable on decel or idle after a hard pull.

I just found out that some other brands of CCV catch cans have larger hoses which minimize the pressure.

So even though I purchased the Radium dual PCV/CCV catch cans, I might only install the PCV side. or maybe just sell the kit (though probably no one would want it...)


I indeed know very little about engines (I am a software guy...) and I am well aware of AI's limitations, and I always double check the actual sources.

All good brother….Yeah absolutely, I installed the PVC Kit. The CCV like “TSP” mentioned is where the headache comes from with their system, the way i see it you have two option, install just the PVC section of the Kit or return it and order this kit instead.

 

[timestamped]

Definitely some confusion. sorry.

There are four different Radium products. AOS-R, PCV, CCV, and the dual PCV/CCV

However, the AOS-R is not made for the FL5, probably since the K20C1 has a built-in Air Oil Separator, i.e. the AOS-R is indeed not needed for the K20C1

Yet you mentioned AOS, which is what got me so very confused. sorry.

Which Radium part did you install?

The smoke issue seems to be from the Radium CCV catch can, where crankcase pressure goes positive causing oil to get past the seals into the hot side, burns on the turbine, and exits as smoke, especially noticeable on decel or idle after a hard pull.

I just found out that some other brands of CCV catch cans have larger hoses which minimize the pressure.

So even though I purchased the Radium dual PCV/CCV catch cans, I might only install the PCV side. or maybe just sell the kit (though probably no one would want it...)

I indeed know very little about engines (I am a software guy...) and I am well aware of AI's limitations, and I always double check the actual sources.

Grok has this backwards:

Dual units for targeted capture (PCV for boost/load conditions, CCV for idle/low-load). Each ~0.5-1qt capacity; modular for easier placement in the FL5's tight bay (e.g., PCV near turbo, CCV near valve cover).

It’s not reliable to ask A.I. things unless it’s not critical that it be correct. Better to query the forum for a response from human intelligence.

An issue with the CCV can implementation is the length of the hoses. An issue with the PCV implementation is a lack of check valve between the can and intake manifold, because the factory PCV valve protects the crankcase from seeing boost, but not the can. Radium says their can will withstand boost pressures, but it doesn’t need to, they are just woefully not open-minded. Hence, most of their stuff is complicated by adding additional needless points of failure that they must think looks cool.

 

[Superhatch]

It’s not reliable to ask A.I. things unless it’s not critical that it be correct. Better to query the forum for a response from human intelligence.

x2. I don't want to get too deep into it here but AI is shit, stop using it.

 

[Clark_Kent]

I decided to hop off the fence and pull the trigger on the @COBB Tuning Redline Carbon Fiber Intake. The sale was really good and the customer service even better from @SBX Performance. I will absolutely repeat as a customer.

@02SilverSiHB thanks again for your perspective on this intake, super helpful. Car looks fresh btw, one of the nicest FL5s out there.

Here are a few not so helpful photos, but I'll provide more insight and proper photos in the coming weeks once I get it installed and the car tuned.

 

[zumbooruk]

Grok has this backwards:

Dual units for targeted capture (PCV for boost/load conditions, CCV for idle/low-load). Each ~0.5-1qt capacity; modular for easier placement in the FL5's tight bay (e.g., PCV near turbo, CCV near valve cover).

It’s not reliable to ask A.I. things unless it’s not critical that it be correct. Better to query the forum for a response from human intelligence.

An issue with the CCV can implementation is the length of the hoses. An issue with the PCV implementation is a lack of check valve between the can and intake manifold, because the factory PCV valve protects the crankcase from seeing boost, but not the can. Radium says their can will withstand boost pressures, but it doesn’t need to, they are just woefully not open-minded. Hence, most of their stuff is complicated by adding additional needless points of failure that they must think looks cool.

my understanding, based on following the links the grok provided to forum and discussions, was that the issue with CCV catch can is on deceleration (i.e. low-load), where the the constriction in the hose causes positive pressure which pushes oil via the turbo bearings.

is that not correct???

I use Grok as a search and summarize tool, I do not ask it to "think" or "reason" (since it usually gets it wrong) I then follow the links it provides to read for myself. it is much more efficient/faster than searching Google one forum or discussion at a time. AI is a tool that when used correctly is very helpful.

Grok has much improved in the last few months. zero hallucinations to my queries.

But note that my custom instructions to grok are about two pages long...

When I worked on genetic programming and artificial neural nets in the early/mid 1990's I called it "definitely artificial, and definitely not intelligent".

I still stand by that statement today and for the far future. AI will never think nor reason nor have emotions, though it will fake it fairly well.

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