This is not THAT confusing is it? Running a breather/vent catchcan or running the vent lines to the exhaust will do the same thing -- eliminate crankcase pressure from buildng up.

By routing the lines to the exhaust, you get free vacuum. When there is vacuum pulling out the crankcase, there is 0 pressure. When you use a breather for venting (no vacuum) there is still noticeable pressure because it has to push its way through the breather filter and lines. In the performance perspective, vacuum helps. Is vacuum NEEDED? No, but it helps. It's an easy thing to do and easy benefits, why not give it some vacuum?

The exhaust gases will not back up into the motor because of the checkvalves. If there is exhaust backing up those lines, then I bet you must be running a 2" exhaust or something.

Exhaust PCV evac setup is proven to work. No, it is not weird and it always work. Ever try hooking up a vacuum gauge to the breather lines on an exhaust PCV setup? You get a nice 4 inches of vacuum pull all the way to redline at peak boost. The faster the exhaust is flowing, the more vacuum it tends to create. So this setup works for engines basically at all power ranges -- 800WHP or 100WHP, it shouldn't matter because the exhaust will be sized accordingly to power output.

Re: Re: (msmotorsports)
 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by msmotorsports &raquo;</TD></TR><TR><TD CLASS="quote">You really don't want to T the 2 breather lines into 1. The whole purpose of having mulitple breather lines is to get the max blowby out of the crankcase. If at all possible put in 1 bung per breather line.</TD></TR></TABLE>
Even if I use an -8AN line? I will look into 2 bungs tho.... https://honda-tech.com/forums/images/smilies/emthup.gif

Re: (Tony the Tiger)
 

so what kind of tubing should you use? will the exhaust burn up rubber? or would it be better to run a length of steel line then hook up a hose to that? and would that be okay to use with boost?

Re: Re: (ferio 95)
 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by ferio 95 &raquo;</TD></TR><TR><TD CLASS="quote">Ok so did you retain the original pcv hose to the intake manifold then tap another one in? Also explain the purpose of the check valve. is that like an inline catch can?</TD></TR></TABLE>
I have a JG/Edelbrock IM, so I completely eliminated tapping into the IM. As we all know, stock PCV from the block goes into the black box, then to the IM. Instead of running it into the IM, I'm going to tap into the valve cover breather which is tapped into the exhaust pipe.

The check valve is just a safety feature just in case the exhaust gas decides to go up that way. Eventhough there is only a slight possibility that this may occur, as long as the car is running since the streaming exhaust gas will be there to maintain a vacuum effect. One other thing to keep in mind is that, heat rises. Upon shutting down the motor, I do not want <u>extra</u> heat from the exhaust pipe to travel upstream leading to the valve cover and/or block.

Also on the picture I posted, noticed that I gave the bung a little angle of close to 120 degrees instead of a straight 90 degree tap. I think that this will aid in a better "vacuum effect"...... https://honda-tech.com/forums/images/smilies/emthup.gif https://honda-tech.com/forums/images...es/emsmile.gif


Modified by thermal at 2:36 AM 4/13/2005

has anybody hooked up a vacum guage to there exhaust to see how much it will suck on a na motor stock or modified?

Re: (pearlcfcivic)
 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by pearlcfcivic &raquo;</TD></TR><TR><TD CLASS="quote">has anybody hooked up a vacum guage to there exhaust to see how much it will suck on a na motor stock or modified?</TD></TR></TABLE>

I haven't tried all motor, but with my current setup, I get a steady 4 inches of vacuum starting from 4000RPM.

Re: (Tony the Tiger)
 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Tony the Tiger &raquo;</TD></TR><TR><TD CLASS="quote">

I haven't tried all motor, but with my current setup, I get a steady 4 inches of vacuum starting from 4000RPM.</TD></TR></TABLE>

not bad, everybody keeps saying its not going to do much but my opinion is every little bit helps... and its basically a free mod

I'm almost done with mine. I'm gonna hookup a vacuum gauge. Pics will be up soon.

Re: (thermal)
 

What happens when you turn the car off though and you don't have the check valves installed, will it then get sucked back up?

What would happen if you had the 2 lines off of the valve cover, then had them routed under the car, but not into the exhaust manifold, sort of just exiting under the car? Would this help at all?

^dude, i dont know how else to answer your questions. Tony the Tiger pretty much covered the whole concept.

I wouldnt just run the hoses like that anyway. Heat rises therefore the fastest way to get rid of it is from the top, nothing else is better unless you hook it up into a vacuum source.....

Re: (thermal)
 

Couldn't find an answer about when the car shuts down?

Exhaust gas will NOT get sucked back up into the motor (PCV) and the valve cover. There is no medium inside the motor nor the head that will cause a vacuum system to suck exhaust gas from the exhaust pipe. A check valve is not really even necessary. PCV valves are one way also. They function as check valves.

Re: (thermal)
 

thermal, when you are done, we should meet up, id love to check out your setup. https://honda-tech.com/forums/images/smilies/emthup.gif

Re: (k4ff1n3)
 

Okay okay....I got tired of reading so if some of this was already covered, I apologize. Lets start by defining what a "breather" actually does. With the illustration posted earlier(which is 100% correct), with the exhaust gases leaving the engine, it creates a natural suction going outwards, which in turn, if a line is connected to it, and also connected to the valve cover, then it will, to an extent, pull, and remove some of the excess pressure in the crankcase, and also on the top end of the motor. Honestly, to run a vaccuum pump on a honda/acura/any other 4 banger motor, is completely pointless! Unles you a fulltime racecar runnings in the low 9's or faster, the simple breather tube off of the valve cover is more than adequate. If your motor is a daily driver, and not FULLY FULLY built, again, you will probably see no gains once so ever. What it actually does is relieve the crankcase, because as the pistons move up and down, they create a back pressure underneath of them, which causes the piston rings not to seal to the cylinder walls like they are supposed to. A vaccuum pump can be your best friend if your a fulltime racer trying to squeeze every bit of power out of your engine as possible, but DO NOT THINK THAT THE MORE THE BETTER! I have seen vaccuum pumps pull up to 28 lbs of vaccuum, but in about 3 minutes the brand new titanium rods were welded to the crank! So be careful whatever you do. With just the breather lines, you do not have to worry about this, but if you were to run a vaccuum pump, be sure the manufacture knows what it is being used on so they can pre-set it for you. Also, as for oil leaving the engine, going out the headers, as some said, its not actually an OIL substance, but more of a vapor, which if collected in a catch can, yes will become oil once it settles again, and there is enough there. However, running it to a catch can is somewhat pointless. Just dump it into the exhaust and let the exhaust burn it up, no big deal. &lt;--- referring to racecar engines!

GOOD LUCK EVERYONE!
Kyle

Re: (blueoval557)
 

I think the exh would be a better bet than a vac pump anyways. USe what you have, exh is wasted energy anyways.

Re: (ne3ek)
 

exactly https://honda-tech.com/forums/images/smilies/emwink.gif

Re: (blueoval557)
 

I own a hot rod car on meth making 812hp. I also have a barnes vac pump a regulator an catch can. I pull 11 inches at IDLE. ANYMORE than 13 will pull oil off the baerings . Thats no good. I make 40 lbs of boost and then the system can't keep up . so a pop off vavle blows off any access pressure. Ask any vac expert this is just the way it is on a high boost motor. nothing you can really do. Vac pumps are most affective for na. This pressure is from blow by at the rings not the pistons going up and down. So how tight is your gap will play a big role. And no exhust can not help you at these levels.

Re: (2.0Coupe)
 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 2.0Coupe &raquo;</TD></TR><TR><TD CLASS="quote">And no exhust can not help you at these levels.</TD></TR></TABLE>

If you route it to the exhaust, it's not much different than a pop off valve that you are using because any excess pressure will just escape through the exhaust. Although we are not pushing 800HP, but even if the vacuum (created by the exhaust) couldn't keep up, all it will do is act as another passageway to vent pressure out through the exhaust -- just another path for crankcase pressure to escape. Might be a bit oily, but most guys run an oil separator in between anyway.

Re: (Tony the Tiger)
 

To those who think running the lines to the exhaust does nothing....heres a little something to think about. First....if youve ever gone to a race where REAL cars are being raced(stuff with more than 4 or 6 holes)...you will see these ALL OVER sportsman cars. You think they would be all over the place and still be selling if they did nothing? I will have to look for an older article from about a year ago in a drag racing mag I have, discussing all this stuff. We run them breathers on our Mustang which runs 8.80's, ALL MOTOR, single 4 barrel...and have had great results with them! As for the exhaust not keeping up....lets see...just slowly being released out of a breather on the valve cover, or having SOME SORT OF SUCTION, maybe not a ton but SOME....I think a retarded person could figure that out. Sorery for the attitude, I just hate people try to diss others, and say they dont know what they are talking about, when in fact, they have the wrong info themselves. And for 2.0.....I understand that the crankcase pressure is because of pistin ring blow by....but lets see...if the piston doesnt move up and down, there probably wouldnt be any blow by right????? Hmmmm....lets think about that one. And if your wondering...YES I AM ALL FOR AMERICAN CARS....NOT INTO IMPORTS AT ALL....but stay around here, and only in this forum to help people out who enjoy the same passion I do....welding and fabrication.
Kyle

Re: (blueoval557)
 

you sound like a nut job

anyway you can clearly see the concept being used on a low displacment 4 cylinder engine designed to make max power

http://www.we-todd-did-racing.com/we...MXk1NDE%3D.jpg

Re: (stormy)
 

thats a great pic! where do i find a check valve like that ?

Re: (ne3ek)
 

engine masters mag did a write up and dyno with a few diff vac pumps on a few diff motors. I havent had a chance to read through it yet but it looked to be some good info.
just a heads up.

m. https://honda-tech.com/forums/images/smilies/emthup.gif

Re: (ne3ek)
 

here is Summit's evacuation system
http://store.summitracing.com/...w=sku

stan

Re: (accord387)
 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by accord387 &raquo;</TD></TR><TR><TD CLASS="quote">cars come stock with pumps to remove crank pressure (i dont think hondas do though) lots of cars run set-ups to remove crank pressure. i dont know how most people on here do it, but from what i've been told people fab up mounts for a pump, run it to the exaust so the exaust provides a suction. (this is what i was told so im not backing all of this 100%, but 99% haha)</TD></TR></TABLE>

honda has a PCV valve...pressure control valve. https://honda-tech.com/forums/images...es/emsmile.gif

Re: (thermal)
 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by thermal &raquo;</TD></TR><TR><TD CLASS="quote">Exhaust gas will NOT get sucked back up into the motor (PCV) and the valve cover. There is no medium inside the motor nor the head that will cause a vacuum system to suck exhaust gas from the exhaust pipe. A check valve is not really even necessary. PCV valves are one way also. They function as check valves.</TD></TR></TABLE>


The sucking of exhuast gasses are EGR. But the pcv takes crankcase gasses and reciculates them back through the intake and burns them. crank case gas is just blow by that everycar has.