KA-T

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The purpose of the catch can is to collect blowby from the PCV system to keep it from going into the intake manifold and being burnt.
So you need to find your PCV valve. Factory there is a hose that connects this directly to the intake manifold, instead connect a hose from the PCV valve to the catch can, then a hose from the catch can to where the PCV valve connected back to the intake manifold.

This way any blowby is first pulled through the can, where the particles can settle out, then the air is pulled back into the engine and burnt.

If you have a turbo car you need to do some interesting hose configurations. On my car the old PCV valve was drilled out and runs from there to the catch can. The other opening on the catch can runs to a T. From the T one hose goes back to the intake manifold with a 1 way check valve in place so that it will suck into the manifold under vacuum, but do nothing under boost. The other open end of the T is connected by hose, with a check valve, to a fitting before the turbo, this way the vacuum created between the air filter and turbo will suck the blowby into there under boost conditions, while not allowing airflow under vacuum conditions.

Hope that makes sense!

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MSD coils, S13 cam, Intake stuff, stainless braid oil lines + more!

i have a s13 blacktop sr20det with a breather on my T already oil stained....

You want to get rid of that breather and attach that fitting on your valve cover to your turbos air intake. This will suck the blowby gases out of your crank case and keep your oil cleaner, longer.

Brand new Borg Warner S258, AKA The Better Than a GT-R Turbo( )---> http://forums.nicoclub.com/zerothread?id=354932

-------->hooooldd, i think i'm okay, i understand the point of it just suck at explaining it. i just hate being corrected

thanks! krazydriver

Modified by 240sxvaj at 1:39 AM 7/17/2008

Modified by 240sxvaj at 1:39 AM 7/17/2008

First thing to realize is that the PCV vents the crankcase, NOT the valve cover. Reason being you get blowby in the crankcase.... if you've got it in the valve cover
The valve cover breather NEEDS to be able to breath either from the intake piping BEFORE the throttle body if you have a MAF, or if you've got a MAP system just put a filter on it.

Therefore where the PCV system exits the crankcase, you need to put the catch can in line between the crank exit and wherever your going into. The factory PCV system hooks directly back into the intake manifold AFTER the throttle body (this way it sees constant vacuum). Only problem with this is on a KA-T there is boost in there, and pressurizing the crankcase is not something you want to do, seals *could* pop out, but pretty much it's not venting anymore and your oil quality goes to hell.

As i described before, using check valves you can create a system where under vacuum the air coming through the PCV is pulled through the intake, with another hose connected between the turbo and filter for boost conditions. This is the ONLY time that location(turbo - filter) will see vacuum, so if you have just one line hooked up between the turbo and filter.... your crankcase isn't really ventilating at all.

Here's a pic of my setup.

Pretty much there is a fitting off the block where the PCV exits that goes up to the catch can. The catch can goes to the T right by the throttle body. One hose of that goes with a check valve oriented so it is only open under vacuum in the intake, the other goes between the filter and turbo where there is only vacuum under boost.

I hope this explains what i'm trying to say a little better.

For the manifold, i just routed the hose from the T back into the factory 4-1 fitting so that it feeds into all 4 runners.

If you look at the parts explosion in the FSM you can see what i'm talking about. I had my manifold off earlier this year, so i took the time to plan all this out before i put it back on.

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r.i.p. Lee
09/01/89~09/28/06

I think a breather defeats the purpose of a PCV system. IMO, you want a slight vacuum on the whole system(as designed from the factory) so when you get blowby gases(positive pressures in the crank case), the slight vacuum created by your pcv system removes those gases and equalizes the pressure of the crank case. If you have a breather, your pcv is going to try to suck out the air with least resistance.. IE, the breather filter on your valve cover. So, your really not removing much blowby gases at all, your just sucking in fresh air down to your PCV valve.

I know with my vacuum PCV setup my catch can was 40 percent full of FUEL after 500 miles, and its not a small catch can at all. I had a blown injector driver that was washing my cylinder wall.... But thats besides the point. Under the worst case scenario, my setup worked wonders.

The fresh air is not going to magically circulate through your engine, its going to go from your valve cover breather, down your front timing cover, and out the pcv valve.

Im not saying that your method doesnt work, im just saying its not ideal.