Catch can for cupra r.19mm??

Stewarty

Active Member
Oct 14, 2016
110
0
Hi all, fitting a catch can at weekend as I've found out my pcv system is a mess(oil everywhere to be what looks like a stuck pcv valve)so I've looked at a couple of guides and it looks easy enough!couple things that wasn't clear or never noticed but is the 19mm the outer diameter of the hoses?and do I just use a new stock elbow from the inlet and does the 19mm hose fit straight onto it?im ordering a can tomorrow so does it matter what size it is?as in 350,500 or 1tr??cheers
 

Cupra Ross

Breaks things............
May 15, 2005
1,380
1
Edinburgh, Scotland
You're better off just replacing the PCV pipework. Catch cans were all the rage when the PCV pipework was more expensive. It's about £15 for a complete set now. Catch cans are a pain, and nothing other than engine bay bling. Run one vented to atmosphere and your car will stink of petrol fumes inside every time you stop. Standard is best in this respect.
 

Stewarty

Active Member
Oct 14, 2016
110
0
Ok Ross cheers for the heads up!yeah I just thought it was the better option when running higher boost but I suppose that's just an opinion I've read up on through forums.i had noticed the factory pipe work is Not expensive and it will be a bit easier and cheaper to just replace the valve and offending pipes,so yeah my mind has been changed!!nice 1
 

Stewarty

Active Member
Oct 14, 2016
110
0
Yeah I did notice that the bam and aum breathers are very similar,think it's just the 1st pipe that comes off the rocker that's different as it has 3 outlets to the aum's 2?i think but yeah I ordered one today and it's the same,a 6 piece kit.will have a look tomorrow at these other pipes and see if I can make out the ones to delete.bit of a novice but will get in there and see what's what.cheers again my friend
 

Andrewwright

Turbo lover
Aug 16, 2016
1,568
224
Peterborough
I'm the other way on this one. Any crap going into the intake is imo bad, nice clean air is good. 19mm is right size for the pipe work needed and mine doesn't smell of anything.

Sent from my Nexus 6 using Tapatalk
 

Stewarty

Active Member
Oct 14, 2016
110
0
Maybe something for the near future then as I've already bot the pipe kit and valve!but just for the record is the 19mm the outer diameter or the inner of the hose.im still not sure about this venting smell as I don't want that atall,would I be right in saying that the bam pcv doesn't vent to atmosphere as it goes back in to the t.i.p or is that totally wrong.novice at work here!!:confused:
 

DorsetChap

Active Member
Jun 3, 2016
43
2
Dorset
Most folk use 19mm id so that's what I used too. The benefits of a catch can are said to be that it catches any moisture and oil emulsion before it's recycled back into the tip where it will ultimately lower the octane of the fuel and be drawn through the turbo, and there's ultimately less pipework to split and cause vacuum / boost leaks. It's also bling if you want it to be (otherwise get a matt black one!). The pipework circuit is crankcase and rocker cover connected, then into the can, then hockey puck valve, then back into tip. No fumes escaping anywhere. Some use a smaller id pipe but there may be an issue with it clogging from 'snot' even though the crankcase is positive pressure (blow by) and the tip is negative pressure. I've used 19mm id (standard) just in case. Downsides are cost and the need to regularly check the can - don't want to draw can contents into tip. The need for this extra check and cost are probably the reasons why cans are not fitted as standard.
 

Cupra Ross

Breaks things............
May 15, 2005
1,380
1
Edinburgh, Scotland
Most folk use 19mm id so that's what I used too. The benefits of a catch can are said to be that it catches any moisture and oil emulsion before it's recycled back into the tip where it will ultimately lower the octane of the fuel and be drawn through the turbo, and there's ultimately less pipework to split and cause vacuum / boost leaks. It's also bling if you want it to be (otherwise get a matt black one!). The pipework circuit is crankcase and rocker cover connected, then into the can, then hockey puck valve, then back into tip. No fumes escaping anywhere. Some use a smaller id pipe but there may be an issue with it clogging from 'snot' even though the crankcase is positive pressure (blow by) and the tip is negative pressure. I've used 19mm id (standard) just in case. Downsides are cost and the need to regularly check the can - don't want to draw can contents into tip. The need for this extra check and cost are probably the reasons why cans are not fitted as standard.

Each to their own. There's only actually one vacuum source on the PCV circuit that could cause a boost leak, and that's the "suction jet pump" vac'd from the underside of the intake manifold. I've had a couple of catch can equipped 1.8Ts and just find it an unnecessary hassle. There's no measurable difference in performance. Can it lower the octane of the fuel/air mixture? Probably by a tiny fraction, and I do mean absolutely tiny. A properly fitted catch can will still deliver most of the PCV fumes back to the TIP anyway.

By all means, fit a tank if you like them, you could buy about 5 sets of PCV pipework for the price of a can though.
 

DorsetChap

Active Member
Jun 3, 2016
43
2
Dorset
There's pro's and con's with either the OEM pcv system or catch can. If wishing to minimise potential boost / vacuum leaks then simplifying the pcv system could be one area to consider. Octane - every little helps. Hassle - I've opted for occasional quick and easy emptying of the can and no pcv boost leaks rather than the hassle of sourcing, buying, and messy backbreaking replacement of the pcv pipework every once in a while. Fumes - a properly functioning catch can will collect most of the liquids and 'snot'. Pull the inlet pipe from your hockey puck valve to see what's going back into your turbo and engine. I'm not saying one solution is better than the other - there's pro's and con's. Each to their own.
 

Stewarty

Active Member
Oct 14, 2016
110
0
Both very valid points guys and as uz say"each to there own!im not really bothered about the bling thing,just want less hassle and no boost leaks!!ha ha,being its a 1.8t!!cheers for all the info tho guys!!defo food for thought.cheers
 
Progressive Parts, performance parts and tuning specialists