AOS-R, UNIVERSAL KIT
SKU: 94903519046

AOS-R, UNIVERSAL KIT

Sale price$118.77 Regular price$131.97
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Ships within 48 hours · Estimated delivery Jul 4 - Jul 9

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Description

AOS-R, UNIVERSAL KITA high powered modified engine tends to generate excessive blow by oil and gasses. In these cases, an ordinary small catch can may quickly fill with oil and not be adequate. Like the Radium Engineering Catch Cans, the AOS (Air Oil Separator) kit is responsible for keeping blow by oil and other pollutants out of the air intake and intercooler (if equipped) systems. The main difference is that an AOS system returns collected oil back into the oil pan so

A high powered modified engine tends to generate excessive blow-by oil and gasses. In these cases, an ordinary small catch can may quickly fill with oil and not be adequate. Like the Radium Engineering Catch Cans, the AOS (Air Oil Separator) kit is responsible for keeping blow-by oil and other pollutants out of the air intake and intercooler (if equipped) systems. The main difference is that an AOS system returns collected oil back into the oil pan so there is no servicing required.

IMPORTANT INSTALLATION NOTES:

-In order for the AOS to function properly, a port must be supplied on the engine for the oil to return through.
-The AOS must be mounted high enough in the engine bay so that the port on the bottom is higher than the oil return port on the engine.
-for heating purposes, engine coolant must be routed to the AOS-R to prevent condensation.

Without a properly designed AOS, water condensation can develop and find its way in the oil pan contaminating engine oil. Engine coolant lines are routed through the Radium Engineering AOS in a specially designed heating chamber (shown above). This keeps the AOS warm and prevents water from condensing inside. Because water is more dense than oil, there is an integrated water trap found around the bottom perimeter that prevents condensation from descending into the oil pan.

For AOS crankcase plumbing, the valve cover vent(s) are routed into the top inlet where the stainless steel condensing material separates the oil from the gasses. The filtered liquid oil is collected at the bottom of the AOS and drawn into the oil pan. Meanwhile, the clean crankcase air can either be vented to atmosphere (VTA) or recirculated to the turbo air inlet pipe. Shown below is a plumbing example.

With a properly operating system, the fluid level inside the AOS will be empty after sitting. If there is a possible return obstruction, simply unscrew the anodized billet aluminum dipstick for inspection. Conversely, the entire billet unit disassembles into 3 large pieces for servicing.

Benefits
-Effectively raises the octane and increases engine performance with cleaner inlet air
-Prevents oil buildup in the intake or intercooler system walls, throttle body, intake manifold, etc.
-Lowers hydrocarbon emissions

Included
-Machined alumium Radium Engineering AOS
-Anodized universal mount that permits 360deg rotation
-Two 5/16" barbed fittings for coolant lines
-Stainless steel hardware

Ports
Top Port: 7/8"-14 threaded for 10AN ORB fittings
Side Port: 7/8"-14 threaded for 10AN ORB fittings
Bottom Port: 7/8"-14 threaded for 10AN ORB fittings
Coolant Ports: 7/16"-20 threaded, includes two 7mm (or 5/16") barb fittings

Measurements
AOS Height: 6.94" (top of dipstick to bottom of AOS)
AOS Diameter: 3.45" Round
AOS Capacity: 20.3 oz (600mL)

Shipping Notes
  • Free Standard Shipping on $100+ Orders to the USA.
  • Except Preorder products are shipped in 48 hours.
  • Delivery to the USA:
  1. Standard Shipping : 3-10 business days
  • If time is of the essence, please consider selecting expedited delivery for faster service.
Exchange/Return Notes
  • We offer a 30-day return/exchange service after receiving.
  • Final sale items are not eligible for returns or exchanges.
  • To process your return/exchange, please contact us at [email protected]
  • Please click here for more details>>> Return & Exchange Policy
SKU: 94903519046

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Mecha Drew
Alexandria, US
★★★★★ 1
I should have read all the other reviews ...
Color: Single Slat Gloss Black, Size: 2010-2013 E92, Color: Single Slat Gloss Black, Size: 2010-2013 E92
I read all the bad reviews, but I gave it a shot anyways Tabs wont clip in place and fitment is slightly off.
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Reviewed in the United States on May 1, 2026
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Charles Sherin
Lexington, US
★★★★★ 5
Worth it
Color: Single Slat Gloss Black, Size: 2006-2009 E92
For perfect and looks great
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Reviewed in the United States on February 5, 2026
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Madison
Massapequa, US
★★★★★ 5
Very nice quality
Color: Single Slat Gloss Black, Size: 2019-2022 G20
I have a 2022 330i bmw and it fit perfectly! Looks just like photos online and delivered quick!
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Reviewed in the United States on August 27, 2025
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Nick
Carnegie, US
★★★★★ 4
Good Item
Color: Single Slat Gloss Black, Size: 2002-2005 E46
Good cost to product ratio, but fitment is a little loose
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Reviewed in the United States on March 9, 2026
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Nolan F. Baby
Lowell, US
★★★★★ 5
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Color: Single Slat Gloss Black, Size: 2019-2022 G20, Color: Single Slat Gloss Black, Size: 2019-2022 G20
Installing this grille was a breeze! It took me about 30 minutes, even with a minor hiccup of having to uninstall it to add the front camera panel I initially forgot. The grille feels incredibly durable, made from plastic that matches the quality of the OEM version. Plus, it gives my car a fresh, youthful look. Highly recommend for a quick and stylish upgrade!
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Reviewed in the United States on May 29, 2025

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