Whats this for???
Hehe, I get that question often! It’s a transmission overflow catch can. I rigged it up when I was doing a lot of TCU tune testing prior to my trans cooler, to ensure hot fluid wouldn’t explode out the top vent.
A lot of TTRS/RS3 guys run these as their vent is in the engine bay and it’ll push fluid all over the engine and up the windshield.
We don’t have as serious an issue but I didn’t want smelly ATF fluid dripping over my exhaust and undercarriage.
Jesus… Always thinking of everything love it man!
I’ll definitely take one after the trial period. If the filters do vent a little then maybe just a small catch can vented in from both valve covers with a Y-pipe, probably wouldn’t have to be a big can. I’m sure you’ve already considered that though.
Sounds good Michel you defo have some great ideas !!
No you don’t want to suck anything up in the intakes lol
Do some testing and keep us posted I’m sure you will tho.
Hopefully it will work ok with just the filters, it would be a shame if you have to put catch cans in I think as that is an added bonus about this mod not having to fit catch cans and no need to be emptying them either 
I would of thought putting catch cans in by the valve covers would not be great as it will be very hot and as i understand it you need it as cool as pos so the oil seperates into the catch can’s hence why @Mblais has his in the bulk head away from the engine heat ?
Is there any need for your transmission over flow now you have the RMR Cooler fitted ?
I know you have had it in for along time now way before the cooler, I actually thought you had taken it out ages ago.
Yeah catch cans work best when the temp differential helps create condensation.
Did my first test drive last night. No oil smell with the windows down or up with the a/c on. No dripping oil from the filters either. Want to put more miles on it before the block-off adapters are done.
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Whooooo yes dude that is ace news !!!
No smell and no oil you is da man !!! 
Can’t wait to get these on my car the filters look ace on top better than the black plastic pipe, I’ve always thought they shouldn’t be there and now they don’t have to be 
plus you are reducing the carbon build up.
How did the car run any difference at all ? As now your not pumping all that crap back in to the intakes.
As soon as your happy with everything get sending me a kit asap please buddy 
Let me run it to redline a few dozen times first, LOL. I’ll be out and about tomorrow, possibly tonight after I’m off the day job.
Doesn’t run any differently but it also rocketed into the 90’s this week so it’s already stupid hot here. And it’s April. Usually doesn’t get this hot til June. So the temps haven’t been stable and it’s hard to assess whether the lack of contamination in the intake charge is enough to have a noticeable, seat of the pants feel. Doubtful you’d be able to even tell but we’ll have to wait and see.
Ok buddy sorry I’m getting a bit excited lol
Thanks for the updates I’ll be watching out for more from you… so go get testing 
You are in the 90’s already ! Oh my days it’s been snowing here in the U.K down to -2/3c at night in April !! Don’t fancy a house swap do you ?
Let me know if you need another tester. I am familiar with VTA smells in my 335is as I have a dual catch can setup on there. I can find a reason to test drive a hundred miles.
Sounds good, hoping to have an update on the block off adapters tomorrow.
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Any updates yet buddy ? I need to spend some penny’s with you it’s burning a hole in my pocket lol !
Well these’ll be cheap so you can use your spare change!
With that said, as I mentioned in the flywheel thread, I did a 2-hour drive to adapt the clutch. It was a relatively cool evening, beautiful in fact, so it was a windows down affair. But I flogged her and didn’t really notice any smell.
Come Monday, it was as hot as dogs balls (technical term) and I ran stop and go errands. Sure enough, I could smell it after getting back into the hot car and starting her up. My theory is without airflow, the vapors have time to accumulate under the hood. When you start the car and turn on the a/c, you’ll get a whiff unless you hit recirculate right away. But that’s the only time I’ve ever smelled it. Once moving, I don’t notice the smell.
We’ll be test-fitting on a friend’s car, probably this week. We worked out expansion rates for different materials and it looks like aluminum will work which is also good news as we then don’t have to source the exact same plastic (can be tough these days with COVID).
Sounds very promising then, that’s fab news
I might not have the smell at all over here in the U.k as it doesn’t get as hot here, we are lucky to see 27/ 28c and that’s not often at all. Also mine smells anyway with not having any cats at a stand still so I doubt I’ll even notice lol
The main thing is you have had no oil from the filters even when pushing hard fantastic !!
Good news on the materials you can use and get hold of as I know it’s not easy atm.
I think you need me to do some testing over here in the U.K as it’s a lot colder here and the air is quite different 
Give me a shout as soon as you have a kit ready as I defo want one asap from what you have said I’m happy to go ahead. What size filters do I need again ?
Thanks buddy
A little bit of smell is fine, us Catless guys are definitely already smelling it strong on startup and especially at Cold idle enrichment. So we are definitley in the proper startup and drvie category for proper warmup.
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I wonder how bad mine will smell since I have the filters on top of my catch cans and they are right beside the cabin filter 
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I’m surprised you can’t smell it now!
I haven’t driven the car yet did the mod in the winter still waiting for the roads to be cleaned lol
Oh gotcha! Didn’t realize…I talked to someone else, can’t remember who…but they had a similar setup and they placed the filters next to the HVAC intake like yours and they could definitely smell it.
Fack ahaha
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