its not NPT (or at least not the NPT i had around the house). The eliminates almost every barb I have found. No wonder why people just drill them out. A new valve from nissan is only ~12$

in for thread size

 

No it's a straight thread, not NPT, with an O ring as I recall for the seal. I want to say 22 mm but perhaps that is just the socket size. Not really sure how you'd determine even if you get a spare PCV valve ($12) or take out the stock one to measure. It's hard to find fittings that size that are straight thread metric to try out... I would just buy the part from local Nissan dealer and drill out the back side. The internal valve component just falls out and you have a nice plastic fitting.

 

ok - so are you guys just drilling it out and then running that right to the catch can directly as well?

 

I removed the PCV completely and retapped the hole with a 3/8" pipe thread tap, and installed a 5/8" barb.

Tomorrow I'm redoing it though, gonna ditch the rubber tubing and barbs and go with -10 AN fittings and SS line. I'll be sure to get some pics

 

if you do an fittings, then you can definately get straight thread metric fittings for it from like anplumbing.com (not that important if you retapped already)

i might just tap to 3/8" myself. The ID of that stock PCV is tiny.

 

thanks Chris - do a write up if you can, I probably will just copy it if it works for you

question - any opinions on the best way to convert the valve cover to an AN? Or is it not even possible?

 

covert to AN is easy. anplumbing.com sells metric to AN fittings as well at NPT to an fittings.

 

but the valvecover is neither metric nor npt, it just has plastic nipples

 

The plastic nipple on the passenger side unscrews.

 

ah that's cool...I assume you mean the one up front? Does the corresponding driver side front nipple unscrew too? any idea if the rear one (that faces the firewall) does as well?

thanks guys - I got my catch can yesterday (really nice too and not expensive) and I'm going to map out the braided hoses today

 

The passenger side one is up front and I think will unscrew with a 22mm socket. The driver's side one is in the back and is a 5/8" nipple and does not unscrew as I recall (built into the ABS plastic). There is no driver's side nipple up front. There are two built in (fixed) nipples that connect the left and right valve covers up front - you could tap into that also, but few do. I would get more oil sucked out of there than I wanted when I tried - perhaps it is not baffled as well to serve as a port for flow in/out of the crankcase.

 

I've been pretty busy lately, but I managed to find time pull the valve covers and drill/tap for the -10 into 1/2" pipe fittings.

 

i'll prolly try 3/8" npt as thats what i have around. close to 1/2"

r u just piping those to a catch can?

I think hoses pipes under the car is a more simplistic solution

looks great.

 

I think i get what you are asking... you are talking about the crossover between the the 2 valve covers. I think those are glued on to the valve cover. there is a member on here (dont remember who) that drilled and tapped for AN fittings.

 

quadcam did that. prolly not worth the hassle though. thats just to equalize pressure between the heads. simple breather there or the stock hose is just fine.

some people T that and attach it to a catch can under vacuum. that would work, but AN fittin and than just to a nonpressurizes catch can is just spending money

 

Yes, it's going to my catch can.

I agree, just dumping the hoses underneath the car is the simplest way to go, but I don't want a ton of oil/sludge building up everywhere. Plus the SS lines into the catch can looks sooo nice

 

thanks

and the rear breather on the driver side cover, is that threaded in or glued? If threaded, anyone know the size?

 

it's part of the valve cover (molded) if i remember. I'm not a guru but i just had the engine out and i think the nipple was actually a part of the valve cover.

 

I think you're right as well

 

i can take a look at my stock block on the engine stand in the garage when i get home but i'm sure someone else will have a picture up before i get home (working the hospital until 11pm)