A simple (I hope) PCV/catch can question

[mk2davis]

I know this subject has been covered and covered and covered...

I did read PCV info , yet I still have a question.

I want to install a catch can in between VC and IM, and if I read the article right the order goes VC -> PCV -> Catch can -> check valve -> IM

I understand the reason for installing the check valve in between the CC and the IM.

What I don't understand is why keep the PCV in between the VC and the CC. Isn't the PCV and check valve doing the same thing, as the PCV is a fancy check valve? If so, why have both? It seems like this is impeding the flow unnecessarily.

I already have a CC in between the VC vent and the preturbo.

Thanks for helping me understand.

 

[CutlassJim]

You are correct. Except I would say the PCV is a very unfancy check valve. /ubbthreads/images/graemlins/rofl.gif

I have just a barb going to my valve cover.

I also had a weird situation where I have very low vacuum and the PCV would rattle and sound like a ball bearing in a paint can. Bye bye

 

[mk2davis]

CutlassJim, do you have to pass smog in NH? I'm wondering if I'll have trouble with the smog check in CA if the check valve isn't technically a PCV. I'll probably save the stock piece for the biannual event.

I saw on JNZ tuning that the pcv fitting is supposed to be British threads? Did you weld onto the VC, use the fitting from JNZ, or do something else?

 

[tektic]

I drill and tap to 1/4" npt. I used over size barbs and a matching in line check valve.

 

[CutlassJim]

We do not have a "smog" like some states have. And the car is considered an antique in NH so they are even more lenient. And the owner of the garage is a friend and also owns a GVR4.

I used another one of the fittings that's on the IM side of the PCV. Same thread and same hose size.