catch can question

Discuss the RB20, RB25 and RB26 series engines.
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Joined: Thu Dec 09, 2004 12:01 pm
Car: Twin Turbo-shaft UH-60L, 1992 RB-240sx

catch can question

Postby bmadd2402 » Sat Jan 06, 2007 10:17 am

OK, there are like 50 different ways to do this, and all the threads are pretty old, so I'd like some new ideas, if possible. I actually have 2 questions. My first: I plan to make a new intake pipe to replace the rubber tube, and was wondering if not plumbing the line back to the inake pipe after the catch can would hurt anything. for example, have the hose come off the rocker cover to the catch can and thats it, or must it go back to the intake? Second, if I did that, I could block off the pcv and the crankcase would just vent to the catch can, right? Would this create an oily mess in my engine bay? I'm sure this has been covered before, but I just needed to ask in my own words. Thanks for any help.

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Re: catch can question (bmadd2402)

Postby Darius » Sat Jan 06, 2007 12:35 pm

You don't have to run the catch can exit back to the intake before the turbo compressor. That is option 1. Option 2 is to simply put a breather on the catch can where it would have normally run back to the intake.

It depends on your catch can, but I have a Greddy and I would recommend using teflon tape on the threaded hose barbs or oil vapor will blow by those and make a mess. The breather filter theoretically catches that.

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