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Tanzimur
03-31-2015, 10:30 PM
Al rite yes i know theirs a bunch of questions out there but no DIY on how to run a catch can setup on an AEB so i wanted to make sure im doing this correctly so i can make a diy afterward.

So lately been cleaning up a bunch of crap in the bay lately and i realized i want to run a catch can setup or dump to the ground for the mean time to make everything nice and cluster f**k less lol. So first off how exactly do i run a catch can less, straight dump to the ground setup???

Do i remove the hard pipe to the tip and plug the hole on the tip where the puck went then plug off the hole where the other end of the pcv pipe went into the three way section where the pcv lies and im good or am i still missing something? Please explain.

Tanzimur
03-31-2015, 10:44 PM
Pic for attention after i remove the hard pipe and plug the tip what do i need to do here? to vent into atmosphere?
http://i19.photobucket.com/albums/b154/walky_talky20/DSC05104.jpg

B5A4coastie
04-01-2015, 03:36 AM
If you want a catch can, then I suggest IE, their kit included everything I needed and came with fancy instructions. As for the dump method, I'm pretty sure people just run a line from the block to under the car and let the crankcase pressure and gravity do it's thing.

The IE kit comes with a metal piece to replace that elbow you have in the picture. I would recommend buying that part and running your dump from there (so the plastic piece doesn't break do to stress)

xdewaynex
04-01-2015, 04:47 AM
The black elbow you have shown in the pic, you can basically get a hose that connects to it and run it down under the car somewhere. I used a couple of zipties and secured mine to the rear portion of the subframe. Your elbow looks in pretty good shape that you might not even need the 034 Motorsports block breather adapter. You can eliminate the rubber T coupler and hardpipe in the picture.

Tanzimur
04-01-2015, 06:30 AM
Cool thanks for the reply guys so just remove the hard pipe and t and run a hose and dump under subframe so i dont get that discusting vapor smell lol? And i should be good without a pcv in boost? Just to make sure

Murph_129
04-01-2015, 06:31 AM
That's not his picture. It's from Walky_talkys guide on refreshing the PCV system.

Believer
04-01-2015, 07:04 AM
I just want to post my experience here regarding venting the PCV to atmosphere.

When I vented my PCV to atmosphere and had no vacuum on the crankcase to help pull the vapors out, I experienced high crankcase pressures that began to blow out around my oil fill cap. My car is a 99.5 and thus has no vent on the valve cover, so that could also be lending to this issue. However, it is my understanding that having this high of pressure in the crankcase is not desireable, so I oped to put my PCV system back to the stock configuration.

Tanzimur
04-01-2015, 08:25 AM
Ye but mine is a aeb i also dont have the valve cover hole and when i did get my a4 my crankcase was cracked so bad that it was wide open to begin with and i did not notice a problem what so ever having to do with high vaccum... And i do plan on running a catch can withn a few weeks or so after i do this dump...

blitz2190
04-01-2015, 08:35 AM
weld a venturi into your exhaust after the rear o2 and use that to pull vacuum from a catch can(which you can make with about $10 at the hardware store), much better than dumping oil on the ground and smelling like ass. not to mention an engine runs better with the crankcase under vacuum.

Tanzimur
04-01-2015, 10:17 AM
Ok so now how would i run a catch can setup with the pcv deleted

blitz2190
04-01-2015, 10:36 AM
Ok so now how would i run a catch can setup with the pcv deleted

the way im doing it on my 2.7 is run the crankcase vent and head to a catch can then a vacuum tube from the can to the the exhaust venturi after the cat.

Tanzimur
04-01-2015, 01:16 PM
Ok but how does that exactly work? The whole concept

blitz2190
04-01-2015, 01:17 PM
instead of the vacuum coming from your intake or tip and sucking oil through the intake, it pulls it through the catch can and burns what little is left through the exhaust.

something like this
http://i140.photobucket.com/albums/r34/saaber1/IMG_28312.jpg

gets welding in like this
http://i140.photobucket.com/albums/r34/saaber1/IMG_28512.jpg

so that the 45* angle is parallel with the exahust wall and that slit is just below so the air can go through it and when the gases rush by they cause a vacuum effect.

Tanzimur
04-01-2015, 01:41 PM
Ahhh i see thank you for the pictures i think ill go with that setup for aure but just to know for future ref how else would i hook up a catch can not doing it the venturi way?

blitz2190
04-01-2015, 01:57 PM
just put it before the pcv valve that goes to the tip, same principle, and will filter out most of the oil vapors. And some just don't pull a vacuum and dump to atmo but that tends to have negative effects on an engine, mainly new oil leaks from increased pressure. Not to mention smells like ass.

Tanzimur
04-01-2015, 02:14 PM
Not really grasping the idea can you make it thorough? Thanks

Avant Nate
04-01-2015, 02:28 PM
Take all of this off:
http://i19.photobucket.com/albums/b154/walky_talky20/DSC05104.jpg
Buy this
http://store.034motorsport.com/block-breather-adapter-audi-volkswagen-vw-1-8t-billet-aluminum.html
Tubing>catch can>tubing >pancake valve>tip

Tanzimur
04-01-2015, 02:44 PM
So theres no way to run it without keepn the pancake and running mani lines? Cause im trying to keep it sinple and clean

blitz2190
04-01-2015, 03:11 PM
3 options
1. Catch can inline with above or stock setup
2. Venturi
3. Dump to atmo

No offense but if this confuses you, you shouldn't be doing the work, have a mechanic do it and learn through research.

redline380
04-01-2015, 03:12 PM
And some just don't pull a vacuum and dump to atmo but that tends to have negative effects on an engine, mainly new oil leaks from increased pressure.

Sense. This post makes none. You dont increase pressue by failing to run a valve. There just isnt a valve. But it does smell occasionally

redline380
04-01-2015, 03:14 PM
If you want to run the pancake valve, simply run a line from the crankcase to a non-vented and baffled can, with another line going to the valve.

blitz2190
04-01-2015, 03:19 PM
Sense. This post makes none. You dont increase pressue by failing to run a valve. There just isnt a valve. But it does smell occasionally

Apparently you don't know much about engines then, and I never said a valve(unless your taking about the first part of the post you cut out answering his question about where to put it on the stock system), it's also a proven fact that a crankcase under vacuum produces more power, and failing to pull a vacuum means that blowby is the only air moving now meaning pressure. Dumping to atmo is ghetto cheap way out when you heard form some random person that said it was a good idea.

Avant Nate
04-01-2015, 03:55 PM
So theres no way to run it without keepn the pancake and running mani lines? Cause im trying to keep it sinple and clean
If only connected to the manifold, you would have to run a closed system with a check valve. Problem is, while under boost crankcase pressure would spike. You would have the leakiest engine in town. Running it to the tip provides constant vacuum, albeit lower than the manifold at idle.

Tanzimur
04-01-2015, 04:02 PM
Alrite sorry to everyone i did seem like an idiot i was at wrk now im at home and am actually reading these replys thoroughly and i got it now thank you

blitz2190
04-01-2015, 04:08 PM
Not calling you a idiot, just suggesting you do a lot more research on how these systems work, mistakes on an audi tend to be expensive.

Tanzimur
04-01-2015, 04:19 PM
Ohh ye beleive me i understand i have 2 done engine swaps turbo rebuilds i get it.

pbcrazy
04-01-2015, 04:35 PM
just put it before the pcv valve that goes to the tip, same principle, and will filter out most of the oil vapors. And some just don't pull a vacuum and dump to atmo but that tends to have negative effects on an engine, mainly new oil leaks from increased pressure. Not to mention smells like ass.

Apparently you don't know much about engines then, and I never said a valve(unless your taking about the first part of the post you cut out answering his question about where to put it on the stock system), it's also a proven fact that a crankcase under vacuum produces more power, and failing to pull a vacuum means that blowby is the only air moving now meaning pressure. Dumping to atmo is ghetto cheap way out when you heard form some random person that said it was a good idea.

Not calling you a idiot, just suggesting you do a lot more research on how these systems work, mistakes on an audi tend to be expensive.

just put it before the pcv valve that goes to the tip, same principle, and will filter out most of the oil vapors. And some just don't pull a vacuum and dump to atmo but that tends to have negative effects on an engine, mainly new oil leaks from increased pressure. Not to mention smells like ass.
Before you continue to compliment yourself on your vast knowledge and call people out, you are incorrect. Vacuum is a type of pressure, and taking away vacuum will not cause increased "pressure" in the way you say (yes the overall pressure will be higher, but only in a "negative" manner i.e. the gases are still pushed out of the crankcase when vented). Also, with a crankcase vented to the atmosphere, your crankcase is slightly more pressurized then STP, and will not cause oil leaks without a separate cause. The reason myself and a few others are so against just dumping to the ground is because 1. It destroys the environment for hardly a gain, 2. the lack of vacuum lets the crap oil stay in your crankcase.

blitz2190
04-01-2015, 04:49 PM
Not gonna argue with some kid that has half the experience, refer to the sig, and take your own advice on calling someone out. research performance effect of vacuum vs positively pressurising a crankcase (aka boost and blowby) before spouting off nonsense again. But I'm sure your right and all major performance engine builders, my 15 years as a mechanic, and engine dynamics are wrong.btw by your own words "pushed" indicates positive not negative pressure. Also -hg to even 0 is still an increase incase your math is just as bad.

ray4624
04-01-2015, 05:35 PM
jimmies...they have been rustled.


You can orient the dumped vent line so that when driving, a siphon will be created.
Yes, it is proven that engines will make more power with vac...hence why drag cars have and need vacuum pumps for the crank case.
But its a 1.8t...which doesnt make much or lose much either way with the dumped crang case breather.

Mine has been dumped to the ground for 3 years without issue. I have the hose running parallel to the road right below my subframe to create some vac...maybe.

blitz2190
04-01-2015, 05:40 PM
jimmies...they have been rustled.


You can orient the dumped vent line so that when driving, a siphon will be created.
Yes, it is proven that engines will make more power with vac...hence why drag cars have and need vacuum pumps for the crank case.
But its a 1.8t...which doesnt make much or lose much either way with the dumped crang case breather.

Mine has been dumped to the ground for 3 years without issue. I have the hose running parallel to the road right below my subframe to create some vac...maybe.

It may if placed by the vents on the pan ment to pull hot air from the engine, how much? Not a clue.

pbcrazy
04-01-2015, 05:46 PM
You can orient the dumped vent line so that when driving, a siphon will be created.
Yes, it is proven that engines will make more power with vac...hence why drag cars have and need vacuum pumps for the crank case.
But its a 1.8t...which doesnt make much or lose much either way with the dumped crang case breather.

Mine has been dumped to the ground for 3 years without issue. I have the hose running parallel to the road right below my subframe to create some vac...maybe.


Not gonna argue with some kid that has half the experience, refer to the sig, and take your own advice on calling someone out. research performance effect of vacuum vs positively pressurising a crankcase (aka boost and blowby) before spouting off nonsense again. But I'm sure your right and all major performance engine builders, my 15 years as a mechanic, and engine dynamics are wrong.btw by your own words "pushed" indicates positive not negative pressure. Also -hg to even 0 is still an increase incase your math is just as bad.

If you notice I never mentioned performance except at the end "destroys the environment for hardly a gain", definitely not arguing that. I doubt you are creating any measurable vacuum Ray, certainly not even close to as much as the turbo pulls on the pcv, but could be some.

ray4624
04-01-2015, 05:50 PM
yea i really dont care. it was never the intention.
muscle car guys back in the day dumped it to the ground and there was a special insert tot he hose which created a vacuum when placed along the road way.

99% of the build on here just run the pcv dumped or ran to a catch can and not hooked to vac or routed back to TIP.
I am always a fan of less parts so the dump was good for me.

Tanzimur
04-01-2015, 08:52 PM
yea i really dont care. it was never the intention.
muscle car guys back in the day dumped it to the ground and there was a special insert tot he hose which created a vacuum when placed along the road way.

99% of the build on here just run the pcv dumped or ran to a catch can and not hooked to vac or routed back to TIP.
I am always a fan of less parts so the dump was good for me.

Yes sir got it all done she feels amazing and more responsive!

Tanzimur
04-06-2015, 06:37 AM
Well everything went well as far as vent to atmosphere and so forth but now 5 days later i do have oil leaking out of my oil cap, and now my leak free underside has a nice sweat of oil coming down the front of the block. So i will be reverting back to stock because of those issues cause ive read up on the new crank seals with the spring tension need a weak vacuum in the crankcase to withhold from leaking and that the old style crank seals without the spring tension are better and do not weep under boost and so forth so just throwing it out there for ya guys just an update!

M-Hood
04-08-2015, 08:25 AM
Can always switch to a AWM valve cover that has a vent or just vent your AEB valve cover.


I have been running a catch can setup on my A4 for a very long time, first just venting the block to a catch can and then upgrading to a much larger catch can venting the block and VC. No issues at all with my larger catch can, no smell and no vapor fumes coming from it. I don't even have any traces of oil on the 3 filters I have venting the can. The trick with the catch can is making it so that it has more venting then the lines feeding it.


Having too much vacuum in the crank case is just as bad as having too much pressure and this can happen with the stock PVC system when running a larger turbo that will tend to have more vacuum pressure on the compressor inlet then the stock K03.

blitz2190
04-08-2015, 08:29 AM
Well everything went well as far as vent to atmosphere and so forth but now 5 days later i do have oil leaking out of my oil cap, and now my leak free underside has a nice sweat of oil coming down the front of the block. So i will be reverting back to stock because of those issues cause ive read up on the new crank seals with the spring tension need a weak vacuum in the crankcase to withhold from leaking and that the old style crank seals without the spring tension are better and do not weep under boost and so forth so just throwing it out there for ya guys just an update!

like i said before it needs a vacuum for this reason, run the line from where you vent out the catch can to the tip(turbo intake pipe) for a vacuum.This way it will filter out most of the oil from the air before going back into the turbo unlike the stock pcv.