DIY Catch Can Question
 

Yes... yet another catch can thread.

I found this write up for a DIY Catch can using an air compressor filter. It seems functional, simple and cost effective to me and a fun little project. What do you guys think of the design? Has anyone run a similar set up and can post their feedback.

http://gearheadsmiataclub.net/vB/sho...h-can-breather

I just need to figure out the best way to add another port (2 to VC and one for breather). Maybe just drill and tap the top for a breather port. I'd have to see the filter in person to decide.


Also if anyone has some neat DIY catch can pics post them up please.

Personally i wouldnt use an air compressor filter.. they are made to be strong.. gotta hold at least 200-250 psi of air so they are very heavy duty. Plus most come with too much extras that we'll toss out.. you dont need a 200 psi pressure gauge on ur catch can. Also too many of them are glass.

Heavy duty isn't a bad thing except for weight which isn't critical for my current build. And I wouldn't be using the pressure gauge on the can. I also don't see an issue with glass if its mounted properly in a good location. Unless I'm overlooking something.

But thanks, keep the feedback coming.

Hmm maybe

California Air Tools Water and Oil Air Filter-317 at The Home Depot

or

Husky 1/4 in. Air Compressor Filter-HDA70403AV at The Home Depot

I just realized that if i buy the pressure gauge craftsman one, then there's my breather port. But at $40 before the necessary fittings I might as well get one of the ebay breather ones. Hmm....

I used one before. The acrylic that the clear bits are made from will yellow almost instantly with oil and will eventually crack. Any of them with an auto-drain are a paint to seal. If you dont pay attention to the level and it gets full you'll suck a whole bunch of oil into the intake. They're also kind of a pain in the ass to mount and look really stupid in an engine bay.

thanks for the input. So if I do decide to do this glass > acrylic/plastic. Approximately how many miles did you drive before needing to empty it. I only drive my car on weekends so monitoring it and maintenance shouldn't be too unreasonable.

It wasnt a miata.

I'm running a Husky one that looks almost identical to the second one triple88a posted. That housing is glass and I'm running it in between my breather and my intake pre-turbo. Seems to be doing the trick thus far (~500 miles, if that), though I only have oily residue and no real volume in it yet. It is indeed a pain to mount though and I ended up having to to zip tie mine to my fan shroud. It was the only location I could think of that required minimal work and kept it as far away from the heat as possible (even though it's right behind the radiator, oh well).

Do you guys loop both the pcv and the breather together what?

I don't understand. Maybe I didn't word that correctly. I'm running mine in between the exhaust-side VC vent and a port on the inlet of the turbo.

I think tripple88a is asking what you did with the other valve cover port. There is one port for the PCV and one on the turbo manifold side.

I'm guessing that I should Tee those together and run that line into one of the compressor filter ports, and the other port mount the breather?

You have 2 outlets on the valve cover, you got the pcv and the breather. Do you connect them together and then connect them to the intlet of the catch can and then the outlet to the pipe in the turbo?

whats the benefit of connecting it to the inlet of the turbo vs VTA?

Edit: upon some light research it seems like it would be better to reconnect it to the intake manifold port rather than pre turbo because you'll have slightly oiled air (idk what the proper term would be) running through the compressor and IC before entering the manifold and burning in combustion. Why not bypass all that with a port that already exists?

Vacuum in the engine which helps the pistons seal better.

Yes I imagine this is what you would do. I capped off my PCV side because it was puking oil into the intake in high vacuum. In that orientation you could just drill out/delete the pcv valve, no?

Wouldnt even bother drilling it out, just use a double sided barb.

I wouldnt even use the pcv, that side pukes oil no matter what you do.

Well thats because theres more vacuum on it than the other side however 2 is better than 1.

If you routed the pvc to the air and the exhaust side to the intake manifold the pcv side would still puke oil.