My PCV catch can setup

[earico]

Here is the original thread:

http://www.svtperformance.com/forums/engine-tuning-214/850729-oem-pcv-design-question.html

Now here is what I did for a total cost of around $50.

At the intake side I left it OEM.

I plugged the PCV hose that runs under the lower manifold with a bolt, RTV and clamp.

Then I bought these at the local parts store. The one on the left replaced the OEM PCV valve and the one on the right went on the PCV vacuum port at the rear of the blower.

Here they are with 3/8" vacuum couplings inserted. For the one at the top I reused the OEM reducer that was on the OEM PCV valve.

Catch can mounted to fuse box bracket with bolts and aluminum tubing as spacers. I had to drill and tap a new hole in the catch can to do this. I made the original top hole on the can my bottom hole and then put a new hole higher up the can.

Catch can lid with 3/8" copper tubing and 45 degree elbow. Copper pieces were soldered and tube was JB welded into back of aluminum fitting. Fitting had to be drilled out to fit.

Copper scrub pads inserted.

All finished up.

The path of air should bring metered from the intake and then thru the crankcase and out the driver side valve cover just like OEM. But then it will go into the tubing side of the catch can and have to pass thru the scrub pads on the way out. Then into the back of the blower and into the intake stream. Hopefully this will eliminate all oil in the intake stream and still purge the crankcase. With the lower manifold hose plugged I shouldn't have to worry about boost pressurizing the system anymore and blowing oil out the passenger side valve cover. I believe that hapens because our OEM PCV valve doesn't completely close under boost. A very small amount of air is still getting by the valve.

I am not too crazy about the fitting I used at the back of the blower because it's soft rubber and may collapse at high vacuum but for now it will suffice. I plan to replace it with a much sturdier elbow setup.

 

[Vicious805cobra]

Damn earico I'm likeing your d.I.y write ups, keep up the great work

 

[my92gt]

So what was done to the passenger side?? You can still get oil coming from that side right through the tb to the plenum and eventually to the lower intake manifold..

 

[earico]

So what was done to the passenger side?? You can still get oil coming from that side right through the tb to the plenum and eventually to the lower intake manifold..

My thinking is that with a constant vacuum on the drivers side valve cover that I will not need anything on the passenger side. I have removed the restrictive pcv valve and gone with an elbow on the drivers side. In theory I shouldn't need anything on the passenger side. If this proves to be wrong I will just put a check valve on the passenger side.

 

[raym5_0]

looks good.

 

[earico]

Damn earico I'm likeing your d.I.y write ups, keep up the great work

looks good.

Thanks guys! :beer:

 

[Colt .45]

Nice setup.
What is the cost for this and where did you get the catch can?

 

[earico]

Nice setup.
What is the cost for this and where did you get the catch can?

It was about $50 -$60 total. Picked the can up here: POLISH TURBO OIL CATCH CAN TANK JDM PERFORMANCE DRIFT | eBay

Fittings pictured above were about $3 each.

 

[Colt .45]

It was about $50 -$60 total. Picked the can up here: POLISH TURBO OIL CATCH CAN TANK JDM PERFORMANCE DRIFT | eBay

Fittings pictured above were about $3 each.

Much cheaper than the JLT, steeda etc.

What is the purpose of the scrub pads?

 

[earico]

Much cheaper than the JLT, steeda etc.

What is the purpose of the scrub pads?

The pads act as a filter. They will help catch the fine oil mist.

The air enters the left side of the catch can (side with copper tube). The air will have to make a 90 degree bend out of that copper tube thru one of the holes in it. That will stop most of the oil but for what oil it doesn't stop the pads are the next thing in the flow path. The air will have to pass thru the pads on the way out the right side of the catch can. Oil will hit the wires in the pad, accumulate with other oil droplets and then drain down to the bottom.

 

[AteYourLS]

i did a similar setup the other day, except i bought a air/moisture seperator from home depot for 12 bucks and just put it in between the vaccum lines. works good.

 

[keith89]

i'm debating if i should do this. just cleaned out my intercooler and lower intake over the weekend. It was very oily. I have a jlt catch can on the driver's side now but i'm still paranoid about oil pooling in the lower intake as the pcv line at the lower intake is supposed to recirculate any pooled oil to be burned up(but will also coat the intercooler). i'm thinking of t-ing in my catch can with the lower intake line with a check valve on the driver's side vc so boost does not go in(like a pcv valve).

 

[earico]

i'm debating if i should do this. just cleaned out my intercooler and lower intake over the weekend. It was very oily. I have a jlt catch can on the driver's side now but i'm still paranoid about oil pooling in the lower intake as the pcv line at the lower intake is supposed to recirculate any pooled oil to be burned up(but will also coat the intercooler). i'm thinking of t-ing in my catch can with the lower intake line with a check valve on the driver's side vc so boost does not go in(like a pcv valve).

That right there is the exact reason I did it. I don't have a single drop of oil in my intake stream now and I still have a functioning PCV system. The catch can setup I did leaves the PCV intact but will filter out the oil vapor. BTW the OEM PCV valve is supposed to be a check valve. It closes under boost. Problem is it doesn't close 100%.

The way the OEM system recirculates oil out of the lower is to send it back into the intake stream once the car goes into boost.....via that hose under the lower and the T in the PCV line behind the blower. Well you see how well it actually works now that your blower is off. All it does it get sucked right back in to the blower and pushed into the intercooler. When the oil vapor hits the intercooler it accumulates on the fins and turns right back into oil droplets and goes right back where it freaking started. Plus the oil vapor will reduce your octane. With the high IAT2 nature of these cars that is a no no. I believe that this has been one of the contributing factors to the detonation pictures we see of broken OEM pistons.

The only issue with what I did is that I have a constant source of intake air coming into the back of the blower....ALL THE TIME. Think of it as a metered vacuum leak. My tuner has made adjustments in the IAC integrator and etc and it is almost like stock now. The idle will hang for a split second and the ecu will correct for it. Hey that extra air might actually help a little on the dyno too. We all know the inlet on these blowers is the main restriction.

 

[03 DSG Snake]

If you ran breathers would both the lower and the blower ports have to be plugged?

 

[earico]

If you ran breathers would both the lower and the blower ports have to be plugged?

Correct.

And you must run breathers on both valve covers.

 

[03 DSG Snake]

How has yours been with only plugging the lower side of things?

 

[earico]

How has yours been with only plugging the lower side of things?

It's been great. Zero oil in my intake tract. I cleaned everything in the intake tract with brake cleaner when I did the install. I have been checking it regularly and there is zero oil in my inlet and intake tube.

 

[SVT_Troy]

If you ran breathers would both the lower and the blower ports have to be plugged?

Yup, that's what I did. Zero issues and I haven't noticed a mess everywhere in my engine bay yet. I don't get a chance to drive m car hard though. Maybe a single WOT pull here and there but that's it. I'm happy so far.

 

[ctrlraven]

I used a stainless steel scrub pad and running dual catch cans. I think I am going to end up running a Metco breather setup cause I'm tired of having to drain the oil from the catch cans.

 

[keith89]

That right there is the exact reason I did it. I don't have a single drop of oil in my intake stream now and I still have a functioning PCV system. The catch can setup I did leaves the PCV intact but will filter out the oil vapor. BTW the OEM PCV valve is supposed to be a check valve. It closes under boost. Problem is it doesn't close 100%.

The way the OEM system recirculates oil out of the lower is to send it back into the intake stream once the car goes into boost.....via that hose under the lower and the T in the PCV line behind the blower. Well you see how well it actually works now that your blower is off. All it does it get sucked right back in to the blower and pushed into the intercooler. When the oil vapor hits the intercooler it accumulates on the fins and turns right back into oil droplets and goes right back where it freaking started. Plus the oil vapor will reduce your octane. With the high IAT2 nature of these cars that is a no no. I believe that this has been one of the contributing factors to the detonation pictures we see of broken OEM pistons.

The only issue with what I did is that I have a constant source of intake air coming into the back of the blower....ALL THE TIME. Think of it as a metered vacuum leak. My tuner has made adjustments in the IAC integrator and etc and it is almost like stock now. The idle will hang for a split second and the ecu will correct for it. Hey that extra air might actually help a little on the dyno too. We all know the inlet on these blowers is the main restriction.

i understand how it works. i'm just paranoid i guess. i added the jlt catch can before cleaning the intercooler and lower intake so i'm not sure if it is still letting a little bit of oil through or how well it is working. I'm sure it is a lot less if any at all is getting past. I can always just cap the line if i don't notice any oil in the lines post catch can. So having the driver's side VC constantly under vacuum from the back of the blower will cause tune issues? Maybe i should wait until i get a retune to cap it.