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Discussion Starter #1 (Edited)

I just want to say that me championing IAG products is having experienced first-hand the praiseworthy attention detail they put into their work and their relentless drive for perfection. I’m a staunch supporter for great Subaru shops to be recognized because I’m tired of seeing customers’ hard earned money wasted due incompetent work compounded by subpar customer service!

Firstly, everyone knows the benefits of an AOS/catch can but here are certain attributes they absolutely need to have:
1. 3 ports (one for each cylinder head and one for top of block). Reasoning being this allows for much efficient relief of crankcase pressure.

2.Coolant heated especially in colder climates or else this happens.


This is another reason why you DON'T want to go with the Grimmspeed AOS (Grimmspeed AOS and Cusco Catch Can After Track Review - YouTube)

There are certainly products out there have do fulfill the above criteria, but as I will go into, there are features of the IAG AOS that perches it atop the food chain. I mean why else would IAG bother even releasing an AOS with a market already inundated with AOS/catch cans?

The rather unassuming, plebian exterior of the IAG AOS belies the engineered intricacies of its internal guts:

1. Better oil separation than its competitors. This is the main idiosyncrasy of IAG’s design. Through painstaking testing and poring over the breathing characteristics of the EJ25, this is what they come up with.
  • No vacuum source allowing for slower movement of oil vapors through the can for greater separation.
  • Swirl pot design for slowing internal velocity.
  • Huge breather port to slow the vapors even more inside the can.
  • The superior coolant heated design ensures that the entire can is perfused by heat so condensation won't form in the oil you separate...which is important because you want the oil to be as pristine as possible going back into the engine!
2. The large capacity, up to 1L (Crawford holds 750mL), practically negates the possibility of having the AOS be brimming full of oil during hardcore tracking. Size comparison:


3. Larger drainage port than its competitors so the AOS can empty the separated oil more efficiently back into the crankcase.

4. The ports are machined into the actual AOS, unlike Perrin which relies on Teflon tape for a seal which is known to break down. READ: Oil + hot engine = FIRE not to mention blatant oil loss (Perrin Air Oil Seperator Install/Review - Page 3 - NASIOC), more leaks: Leaking perrin AOS - NASIOC
more leaks: http://www.iwsti.com/forums/4079430-post38.html
More leaks: http://www.iwsti.com/forums/4079908-post40.html
more leaks: http://forums.nasioc.com/forums/showpost.php?p=43064317&postcount=69
Leaksssss everywhere: http://forums.nasioc.com/forums/showpost.php?p=43554374&postcount=105

Furthermore Perrin AOS O-rings needs to be inspected (http://www.rallysportdirect.com/catalog_photos/instructions/perrin/per1_psp_eng_606rd.pdf) whereas IAG uses Viton O-rings that not only withstand the harsh temperatures of the oil but also the potentially corrosive properties of oil (high chemical resistance).


5. Although maintenance-free, it is easily disassembled like Perrin for cleaning. You don't have this luxury with Crawford.

6. Just overall a high quality design, your $370 goes a long way!


7. AOS is better than a catch can. I’ve ran a Peterson catch can for 75,000 miles. Although I was desensitized to the smell, my passengers would comment on the smell of oil. The vapors would come out of the breather filter to condense to an oily film on my surrounding components, aside from looking like sheer filth it could also pose as a fire hazard. There is also the possibility of an oil catch can filling up entirely during hardcore cornering on the track, depriving the motor of all that sequestered oil.

8. IAG AOS will fit even with upgraded TMICs.

9. Why no vacuum source? The main reason is that the engine is under a positive pressure when you are boosting and a vacuum source is not really need while cruising. It also eliminates ANY possibility of any oil getting back into the intake system. The PCV system is really for emissions where it is not emission friendly to dump the vented gases into the atmosphere so they are rerouted back into the intake. As people who modified cars, we don't really care about emissions with our catless downpipe, do we :lol: The IAG AOS is built upon the lack of a vacuum source and it does its job extremely well :tup:

The new IAG AOS V2 will feature an optional vacuum source for those who adamantly want it :)

Comp vs street series - I would choose Comp if you have an upgraded turbo and/or on E85. Street series does decrease the amount of E85 vapors that are able to get into the oil which ultimately leads to drop in oil viscosity and lubrication. You should be changing your oil frequently when you run E85 anyway. E85 vapors are the lesser evil when compared with the higher potential of blowby you encounter with the street series while running bigger turbos/high boost.

10. IAG has the best coolant passage design to ensure that the ENTIRE CAN is perfused uniformly by warm coolant. This of course lessens the possiblity of sludge build up and prevents condensation formation. Perrin only has the base heated.




Personally, this is what my throttle body looks like with 30psi of boost and 3000miles with the IAG AOS (dat pink meth). No smell of oil at all :tup:


so stealthy that the dealership will think it is the 2015 STi sound tube :lol:


Further endorsement from Junior NASIOC - View Single Post - PTE6466 650+WHP Build E85 and

http://forums.nasioc.com/forums/showpost.php?p=44055425&postcount=223 (for you high boost people)
 

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Discussion Starter #6
Are there any advantages to either the street series or competition series? Or should i wait for the V2?
The vent to atmosphere is what the original IAG AOS is where the gases escape directly into the atmosphere and not back into the intake which also eliminates the vacuum source. This how the originally designed AOS was intended to do based on the points I illustrated in my post. Due to the increased clamor for a vacuum source and also some gripes about dumping the gases directly into the atmosphere, IAG obliged and are offering it as an option.

The Street Series will have a vacuum source and reroute the gases back into the intake.

The Comp Series will be the original VTA design :tup:
 

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Discussion Starter #8

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The vent to atmosphere is what the original IAG AOS is where the gases escape directly into the atmosphere and not back into the intake which also eliminates the vacuum source. This how the originally designed AOS was intended to do based on the points I illustrated in my post. Due to the increased clamor for a vacuum source and also some gripes about dumping the gases directly into the atmosphere, IAG obliged and are offering it as an option.

The Street Series will have a vacuum source and reroute the gases back into the intake.

The Comp Series will be the original VTA design :tup:
Between the IAG AOS, Corsa CBE and the girodisc rotors... you're enabling me FAR too much. STAHP. :lol:
 

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To add to this review, I just received my IAG AOS today in the new wrinkle red color! It looks great! The build quality on it is absolutely spectacular! The instructions I got off their site are also outstanding and very through. I will be installing it in the next few days when I get a chance. I would also highly recommend this AOS over all the others; it has the most thought out design for sure!:tup:

If you're wondering where to get it, I purchased mine from SMY Performance. I emailed Yanev before I placed my order to see if they had gotten them in yet and he said they got their shipment on Friday! Awesome vendor, will be doing business again with them in the future! :cool:



Does anyone know if this will mount with a Perrin strut tower bar?
Like User said, contact IAG. But if you look at the AOS there are many holes along the length of it that are used to mount it to the bracket. I'm sure you could get it mounted fine and still use the strut bar... or just get rid of it the bar. It's not really necessary on these cars since the strut towers are located so close to the firewall.
 

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Give IAG a call

You'll get way more function out of the AOS than the strut bar since strut bars don't do anything anyway :lol:
Do you think an AOS (this IAG one, for example) is a necessity when going stage 2 (only downpipe, protune, and maybe an intake)? I am stage 1 now, just CBE and Cobb OTS tune, car runs great and will be going stage 2 as described in the Spring. I have checked my IC for oil and it's bone dry. I'm very well aware of the purpose and function of an AOS, but is it something that should be added if symptoms are observed or when mileage gets high? Or should it just be a standard item that almost defines stage 2 like a DP, etc...
 

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Discussion Starter #17
Do you think an AOS (this IAG one, for example) is a necessity when going stage 2 (only downpipe, protune, and maybe an intake)? I am stage 1 now, just CBE and Cobb OTS tune, car runs great and will be going stage 2 as described in the Spring. I have checked my IC for oil and it's bone dry. I'm very well aware of the purpose and function of an AOS, but is it something that should be added if symptoms are observed or when mileage gets high? Or should it just be a standard item that almost defines stage 2 like a DP, etc...
Any forced induction car benefits from a catch can/AOS because of the positive pressure in the crankcase from boost. The more boost from Stage 2/bigger turbo the more positive pressure and the more blowby you'll have. Blowby lowers octane which leads to detonation damaging the ringlands creating more blowby, it's a vicious cycle. You don't necessarily need it but it does add a layer of protection.
 

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I bought and installed an IAG AOS 6 months ago or so and can attest to its usefulness. Hard to say that it is completely preventative, but I went from a little oil in the IC to zero and when taking apart the AOS, there is a film of oil inside. Definitely happier to see it there over being slurped back up into the engine.
 

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I bought and installed an IAG AOS 6 months ago or so and can attest to its usefulness. Hard to say that it is completely preventative, but I went from a little oil in the IC to zero and when taking apart the AOS, there is a film of oil inside. Definitely happier to see it there over being slurped back up into the engine.
How is it doing in the cold? Lines gumming up at all?

I can't wait to order one of these. They seem to be the best solution for keeping oil out of the intake and in the case.
 
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