Do I connect the breather hose straight from the intake to the valve cover like before to the intake tube going in to the TB? It has a nipple on it, but I didn't think compressed air going in to my valve cover was a good thing .

Do I just plug the hole on the intake tube or what?

jB

 

get a baby breather...small filter that you can get at auto zone they carry ionized red, blue, and a gray....

sometimes you'll get oil in there so i didn't connect it to the intake....


[Modified by 98civicEX, 5:35 AM 8/22/2002]

 

its catch can time.

 

So what about the nipples onthe intake tubes? Do I need to plug them, or is it not big enough to effect boost levels?

 

yes,m plug them. even the smallest hole and effect boost.

 

well, *technically* if you routed it right after the intake filter, right before the compressor, the air wouldnt be compressed would it?

 

Just connect a rubber hose to it and let the blow by gases dump down.

 

What did you do with the rest of your PCV system ? As suggested, you could route a line to the intake piping before the compressor, but since oil would ocassionally spit out... don't do that with a boosted car.

Plug the holes on the intake plumbing (how come your charge pipe has these nipples ? Are you using a brand of turbo kit ?) and put a breather filter on the valve cover opening.

You should REALLY look into getting a catch can setup.... check Summit, Greddy or Moroso and read up on them before you buy.

 

I thought the flow direction was supposed to be INTO the head from the intake tube through the valve cover. In this way, the PCV system takes the (NA, not turbo) intake pressure and purges the oil vapor to the intake manifold. That's where the catch can goes (between the PCV and the intake manifold). By using an input before the compressor, you still get the positive flow into the head, and there won't be any oil going into the compressor. This assumes you have an angled pipe or something to "channel" the flow into the tubing and through the head.....

Or am I totally off track?

Steve

 

...i thought it was opposite (here we go again...) in that the blow by vapors go back into the intake to be recombusted in the engine...

-Rage who is now toatally unsure

 

Ok.....try this....from https://honda-tech.com/zerothread?id=259991

[QUOTEthe valve cover intake is supposed to function as a fresh-air intake for the pcv system. the crankcase vapors are vented out the back of the block via the pcv valve, which opens when it senses vacuum from the manifold. the problem here is that all of that oily crap gets sucked into your intake manifold and into your motor, increasing the likelyhood for detonation to occur.
under boost it's a slightly different story...the pcv valve needs vacuum to open, so when the engine is boosting it closes. that means there is nowhere for the blow-by to go except out the valve cover intake. that it why peoeple find oil on their valve cover breathers, and also why you don't want to run a hose from the valve cover intake to the intake piping (pre-turbo). you could be sucking oily-vapor-blowby right through your whole system under boost when the pcv valve closes and forces the gases out the intake - certainly the worst time to be injesting oil!

some people have told me that you need vacuum to help suck out the crankcase vapors properly, some say they'll come out fine on their own anyway. as we see, that all changes under boost anyway since boost will force the pcv valve closed.

considering all these factors, the best application for FI is proabably:

valve cover breather---->(crankcase)-->stock accumulator----->no pcv valve----->catchcan----->breather (on end of catchcan, not connected the the intake at all)

the closed loop option woud be:

valve cover breather tube connected pre-turbo------> (crankcase)--->stock accumulator----->catchcan----->pcv valve------>intake manifold

the second option will still allow oily vapors back in, just less. (be sure to use a baffled catchcan, or fill an unbaffeled can w/ steel wool). but remember, under boost the pcv valve will still be closed, and unless you are using the valve cover breather you could still wind up with oily vapor in the intkae charge.

anyways, good luck with whatever option you choose.

greg

[/QUOTE]

I forgot that the PCV needs vacuum in the intake manifold to "pull" the oily vapors out otherwise it shuts off. What happens if you remove the PCV? Then you'd have vapor into the intake manifold at all times.

I dunno....there's not a good solution I can see that satisfies the Honda flow design, emissions/environmental concerns and performance with FI.

Input welcomed......

Steve

 

Look, the PCV system that is used in these engines is designed, in particular for the operating parameters programmed into the ECU. The car is MADE to run with this system in place.

Things should NOT be changed in order to maintain proper operation. Yes, the PCV system is ok for the enviroment, but it does make the motor run dirtier in that oil vapors are tracting back into the intake charge to be burned in the next combustion cycle. The main downsides are a hotter intake charge, dirty intake air, less volume available for air to be ingested, and the fact that this oily vapor promotes detonation and nasty intake manifolds.

You should only consider changing the sytem when you change something drastic on the motor.... let's say... swap your header for a turbo manifold, maybe ?

When this is done, after boost, the PCV valve becomes overwhelmed with the excess crankcase pressure... as well as the intake charge being corrupted. Granted, the oil vapors will not be expended while under load, but while under load, the turbo is building internal crankcase pressure, which, while designed to hold that pressure in, the PCV valve will eventually stop functioning correctly... and you'll prolly end up damaging the motor. Which is why you need to use an open loop catch can system on a turbo honda.

AE