I had a similar concern about volume of the canister because they are available in sizes from 500ml up to 3l. Which to chose and why?
The other trick seemed to be specifying the size of the diaphragm and hose nipples.This seemed critical because Porsche use the same(??) AOS for 2.5.2.7 and 3.2l. So the difference is the hoses? Does one have a restrictor in it for specific engine sizes? I have a 3.2L and there are no restrictors in it's OEM hoses. Or is it the engine breather fitting that varies ? Stelan's kit mentions this.Note his kit also plugs one hole in the crankcase and deletes the corresponding hose.

There are inexpensive generic versions of the Mann ProVent -like this:
Universal Racing Engine Oil Catch Tank Can Reservoir Breather Stainless Filter | eBay
and the genuine article here:
https://www.amazon.com/Mann-Hummel-6257511-Provent-200/dp/B01F2NZ6RQ

They have both been on my List for months . I dismissed them because they need modifying to enlarge the drain. Moroso & MishiMoto have some that look easier to modify.
For me the big reason to persevere with this project is because even the OEM replacements can be defective.But you won't know that until you have done all the work of R&R.
I hope Stelan and Jake can figure something out. Based on his response to Jake, it seems like Stelan's system is "One size fits all M96" ??

Yes it is designed to Work with 2.5, 2.7 engines only

Oops, did I miss something. I ordered one of your systems for my car, which is a 3.2. Is this going to work?

i have not tested it in a 3.2, it would be cool if we can see how it does, and if modifications in the volume are needed, do you want to help me getting it dialed in once you get it?
Let me know
Thanks

Same for me (2000 S with 3.2). Maybe "it" above is referring to the other aftermarket system?

I "think" that up through 2002 our cars use the same AOS (99610702304), then in 2003 the inlet to the block got bigger to let the oil drain faster, so that AOS has a new part number (99610702601) and that maybe some of the hoses are a little different too across the years and sizes.

yes to fit both hoses configuration will be a little different I will include both variations hose sizes, the volume on both OEM AOS does not seem to be that different and easy to compensate with hose lenght so we can use the same vessel that fits well in the engine compartment in the mean time I will test it in my friends 3.2.
this AOS drains into the block via the large block opening so I don't see a problem.

If there is a LTFT problem for the 3.2L engines+Stelan's AOS, it will set a MIL code of 017x
Depending on which specific code is set(rich/lean) would help decide what mods to make for the 3.2L The specifics of short/long term fuel trim would obviously be relevant
Good luck finding the tweak necessary to make this work for the 3.2L M96
* For the 3.2L M96, just use the Audi part # 06E103245E -which is the PCV used on the Audi 3.2L engine?It blows the budget but the diaphragm is replaceable!
https://www.ecstuning.com/b-genuine-volkswagen-audi-parts/pressure-control-valve-pcv/06e103245e/

I've got a 3.2 too. Will this be an issue?
I'm not quite clear.

I'm hoping it will not with the adaptations needed but I will know for sure based on some tests in the next few days, If for some reason I can not make sure it works then we will consider it a 2.5 2.7 part only and I will refund the 3.2 guys, no worries. thanksgivving holiday will give me and a few days to play with it.

Can you share more details, the screw and the rubber plug blocks the original small return opening, can you share more about the new bigger location for the oil to drain to?

Original 2.5 and 2.7 AOS drains thru small opening in the block that proved to be a design issue as it does not drain fast enough under certain conditions, this small opening is not used in the stelan AOS as it drains thru the larger intake at the bottom of the manifold. that is why the small opening gets blocked by the plug.

On the 3.2. 99610702601 (later larger drain AOS) I will have the manifold drain thru both larger intake and original larger drain locations for even better oil return as the larger displacement is more demanding. the R&D I have is to do is to make sure system volume is appropriate for fuel trims, etc.

Stelan,
Sounds promising.
Just a thought - the PCV intended for a 1.8L VW may have inadequate vacuum flow for the 3.2L ? Use one intended for a larger engine? See Post 47 for the Audi Part #.
But a generic would be cheaper.

2003/2004 only right? Up through 2002 uses the smaller hole, even on the 3.2? That is what blocks us from using the larger Porsche "Motorsports" dual canister AOS, although I have seen one installation that did it somehow using a hose and a clamp, maybe they drained it to the larger place that you are using?

that's correct, that's why I think I will include the plug so accommodates all situations
the motorsport one besides the need to adapt it's physically huge (in price too lol).

good call however the 1.8t is well capable of flowing more than enough, that is not an issue. diaphragm in both oem 2.5/2.7 and 3.2 are similar, the amount of flow is dictated by the rapid opening and closing vibrations of the diaphragm based on TB pressure/vacuum signal.

This link with graphs and references and FAQ may help others understand what we are talking about:
High Performance PCV Valve Shootout – Flow Test Results | M/E Wagner Performance Products

Fuel trim is the hardest part, and the most important.

This is the thing that has blocked 100% of my attempts to do this for the past decade. Things like deceleration recovery, and extended WOT operation are where the things get hairy the fastest, and this is when the volume of the unit and engine displacement, and output will come into play.

Issues driving down the road normally can be experienced too, and remember, long term fuel trim values can take hundreds of miles to show an issue. This is what takes so much time, since every change to the unit/ design/ etc takes days of driving to actually compare.... A stand alone data logger with a 2 channel manometer is the best tool for this job, so you can plot the vacuum changes in inches of water values. Overlaying that data with fuel trim plots gathered at the same time, and MAF signal can help see the real story of the changes that you made.

The other road block that we've had is far from that of a developmental hiccup, as the AOS is an emissions component, and it's pretty easy to get in trouble when bringing something to market that's considered an emissions related item. I have two products developed for ''tis very issue at the present, but we can't sell them without a large amount of liability and risk.

Maybe these things help stimulate thought on your end.

I have a 3.2 you can use for a lab rat.

Thanks Woody, that is would be awesome, I will come visit you

Stelan,

I have a 3.2 so will wait for you to prepare this version.

Thanks!

Read the last two pages of my build thread to see what you're getting into

I'm impressed with the knowledge sharing and cooperation of you guys.

Had no idea the lowly AOS had to fit so many operating parameters.
I guess its more than just a simple oil trap.

With any development your going to run into some bugs and it encouraging to see that the potential pitfalls have been identified so fixes can be worked out for version 2.0.

Looks like you could have 2+ versions going forward for the different displacements and oil drain arrangements.

Keep up the great work, cooperation and knowledge sharing, that's what makes this forum so awesome along with the fantastic and brainy members.

"A stand alone data logger with a 2 channel manometer is the best tool for this job, so you can plot the vacuum changes in inches of water values. Overlaying that data with fuel trim plots gathered at the same time, and MAF signal can help see the real story of the changes that you made"

Seems Jake has done way more testing of the AOS than anyone at Porsche !
Now I understand why he was able to identify the problem of defective , new ,OEM AOS units.
For the good of the environment, the CARB and EPA should be encouraging such developments ,not obstructing them. Who else is going to develop effective emissions control equipment for a micro-niche vehicle for which the emissions warranty has long since expired ?

How's it going with testing on the 3.2?

Hopefully Stelan has a fix for his kit. We really need a solution to this AOS problem and sadly Porsche OEM is an unreliable answer.
One of the differences between Stelan's system and OEM is the deletion of one 'hole' - perhaps that should be restored ?
"OIL RETURN PLUG
this is a mall rubber hose and screw to block the tiny OEM engine block oil return, this small engine block opening is not longer used and it is blocked with the Stelan AOS system."
Maybe if that hole is used in the 2.0 version of Stelan's system it would help the Fuel Trim problem? Just reconnect it via a Tee at the base of the new can ?

Any additional info on how the testing is going?

I've sent Stelan a few PM's but no answers.

Any updates.
 

I have a 3.2. Any updates? Has anyone replaced the AOS hard plastic accordion hoses with rubber or silicone? I broke the lower and can’t get a new one on without taking the entire top off. If the hose was flexible I could do it in minutes.

[QUOTE=Josephjochoa;562725]I have a 3.2. Any updates? Has anyone replaced the AOS hard plastic accordion hoses with rubber or silicone? I broke the lower and can’t get a new one on without taking the entire top off. If the hose was flexible I could do it in minutes.[/QUOTE


What year engine ?

Here's mine (below). I used clear, and put the large loop in it to hopefully catch any liquid oil that would otherwise cause the dreaded "smoke bomb" at the track. If I pop the hood and see oil int he loop, it's a very easy task to remove it, drain it / wipe it out and reinstall it.
The first effort was simply a nylon-braided-reinforced hose.... but once it was warm, it collapsed under the vacuum. This is a wire-reinforced hose and seems to be holding quite well.
http://986forum.com/forums/uploads02...1547661745.jpg

I like that set up. What is the diameter and length of hose? Where did you source the hose?

It will be interesting to read about the longer term effect of heat/oil on the hose. In theory, wire reinforced Silicone hose may a better choice - if you can find it.

https://www.usplastic.com/catalog/item.aspx?itemid=23600

Not clear but translucent enough to see any oil.

I like it, but still uncertain to me if it'll collapse under vacuum, the way my first one did. But being silicone is a plus, for sure.

Sent from my SM-G930T using Tapatalk

In my experience only the steel wire reinforced tubing will withstand the vacuum in this diameter. The smaller vacuum lines can be thick wall silicone without collapsing but not the large ones we are discussing.
It will be great if the hose shown stays clear colored and does not become brittle. The silicone equivalent is expensive in clear and difficult to find.

Have you seen this? Best solution I've seen so far.

https://www.ecstuning.com/b-ecs-parts/ecs-tuning-baffled-oil-catch-can-8oz/003779ecs05a02~a/

I'm skeptical about the ECS system linked above because many catch can systems have been tried for the M96 and none work correctly - so far. The generic ECS catch can seems much the same as other systems.
The limiting factor on the M96 is reputed to be the low tension oil control rings if you read this and other threads.
http://986forum.com/forums/boxster-general-discussions/31410-aos.html

you can simply run a catch can inline with the hose to the intake manifold. You won't remove ALL the oil, but it may save you if you have a dramatic AOS failure.

The ECS (and several other) catch-can setups have provisions to "vent" back to vacuum, so I don't think the rings are the problem. As I see it, we're introducing volume to the system, but once initial vacuum is built, the added volume is not likely a problem. (I say "not likely" because I haven't tried it myself. there is theoretically a potential for the additional time required to regulate changes in vacuum in the larger volume to create a lag under part-throttle situations?)

For me, the problem with this catch-can is that I couldn't find anyplace to mount it, except in the trunk, and I don't want to do that to my street car.

Why does the catch can have to be mounted in the engine bay or trunk ? Is there enough space down by the transmission ? A hose could extend from the AOS down to the catch can then up to the manifold . This would create a loop of hose plus the can plus the OEM AOS . Crazy idea ?