Exhaust Evac (for the hundredth time)

[Mike M]

Been reading on PCV systems all evening but I wanted to bring up another thread discussing the best way to get this done in an exhaust style evac, there have been a few examples done and posted but I have a few additional questions to add that I never found in my search.

This is for my 88 Lancer Shelby.

First off the WHY, I currently run a regular turbo valve cover with the baffle mod (re-sealed) with a single outlet and absolutely no hose on it, so its free to breathe (vent out my oil mostly, lol). My motor (2.5 wisecos and more) has over 9000kms on it this year alone and has not seen over 12PSI of boost since just last week where I have installed my alcohol injection and have it running at 20PSI now ( makes me smile, actually its frustrating as the tires still have iffy traction through third gear). At 12PSI I would get a little oil most coming out of my valve cover but nothing that bothered me at all, it was expected with it freely venting. Running 20PSI now I get significantly more oil out of the valve cover and after a 3rd-4th gear pull I can smell oil... it is bothersome to say the least.

I have tried a air/water seperator catch can trick on a stock type PCV setup before but was not happy with the results at all as my BOV would vent oil up onto my hood. I am interested in an effective exhaust evac while minimizing any oil/smoke out the exhaust.

It appears most people use the Moroso kit available through JEGS. Shown here ( http://www.jegs.com/i/Moroso/710/25900/10002/-1 ). Both Jegs and Mr Gasket both sell their own version but this one seems to be the popular one so I would stick with it. I know Reeves has used both in one system but that may be a bit overkill for my setup, so one of those would do just fine. I was planning on hooking this to the single nipple on the turbo VC.

What some people mentioned but I have not seen a single example of is a vacuum regulator as I would be interested in installing one to control the crankcase vacuum, Jegs version shown here ( http://www.jegs.com/p/JEGS/756311/10002/-1 ). I had the idea of installing this on the backside of the valve cover near the cam sprocket, out of the way of the intake/fuel rail hopefully. My question regarding this, would you install a filter on this? It obviously opens up to allow ventilation into the crankcase to limit the vacuum on it, but I'm assuming its not a very big orifice, should one be installed to be safe?

Now with a regulated vacuum you should limit the vacuum and hopefully the amount of oil sucked into the exhaust I wanted one more safety that had been brought up but I have seen no examples of one installed. Would a catch can be beneficial in between the valve cover and exhaust check valve? The issue I see here is most catch cans have small hoses (like 3/8s inlets) whereas the standard size for the evac hose is 5/8ths. Would it cause any problems adapting the hose down to run through a catch can? Is a catch can really needed if you are limited the vacuum? Anyone have a link to a good alum (even ebay style) that are not too big even kinda small in diameter? I don't want to have to run 3 ft of extra hose and mount this to the rad support. Just as I was typing this I just had a realization I could run my evac hose across the intake and down the passenger side firewall where I might be able to hide a catch can down on the firewall (I'm running a TU header so room on the firewall on the drivers side is... well, nearly non existent). The check valve could be installed down on that side as well, doesn't matter which side is on as long as its past my WB02 to avoid contamination.

I heard it asked but didn't get a good answer, where can you buy black silicone 5/8ths hose for running the evac hose?

Thanks for any input or any recommendations from the guys who have experience in this department. If you have an evac system, are you happy with it and what would you change? Do you think a setup with all the bits I've listed above be overkill or just right? I'll spend a few bucks to get a good system going if I have to... I know having vacuum on the crankcase should be worth power and better for the motor as well (so I hear) so I'd like to get this done... I want to run higher boost reliably... the oil smell/mess is bothering me.

P.S. Sorry for the long post, I didn't realize I had that much to say

[JuXsA]

Even though my motor is still new I have a decent amount of blowby as well. I have considered running a line from the pcv nipple on the valve cover to a catch can to a nipple on the inlet of the turbo. My big concern though is the amount of vacuum the crankcase will see and how much oil it will suck in. I don't know about running the evac through the exhaust since I am running a cat. I would worry about clogging it up.

[badandy]

Been reading on PCV systems all evening but I wanted to bring up another thread discussing the best way to get this done in an exhaust style evac, there have been a few examples done and posted but I have a few additional questions to add that I never found in my search.

This is for my 88 Lancer Shelby.

First off the WHY,

Because I tried everything else and I have used this setup on two cars now with excellent results. It keeps your oil cleaner due to blowby gasses can more easily escape instead of being trapped and mixing with the oil, it helps your seals last longer as they do not have to deal with the pent up pressure, it helps promote ring seal which is always good for more power...and lastly it's just cleaner.

I currently run a regular turbo valve cover with the baffle mod (re-sealed) with a single outlet and absolutely no hose on it, so its free to breathe (vent out my oil mostly, lol). My motor (2.5 wisecos and more) has over 9000kms on it this year alone and has not seen over 12PSI of boost since just last week where I have installed my alcohol injection and have it running at 20PSI now ( makes me smile, actually its frustrating as the tires still have iffy traction through third gear). At 12PSI I would get a little oil most coming out of my valve cover but nothing that bothered me at all, it was expected with it freely venting. Running 20PSI now I get significantly more oil out of the valve cover and after a 3rd-4th gear pull I can smell oil... it is bothersome to say the least.

I have tried a air/water seperator catch can trick on a stock type PCV setup before but was not happy with the results at all as my BOV would vent oil up onto my hood. I am interested in an effective exhaust evac while minimizing any oil/smoke out the exhaust.

It appears most people use the Moroso kit available through JEGS. Shown here ( http://www.jegs.com/i/Moroso/710/25900/10002/-1 ). Both Jegs and Mr Gasket both sell their own version but this one seems to be the popular one so I would stick with it. I know Reeves has used both in one system but that may be a bit overkill for my setup, so one of those would do just fine. I was planning on hooking this to the single nipple on the turbo VC.

Fair warning: You will need some sort of other vent to allow the motor to breathe in as well as to exhale when you let off the throttle as the one way valve in the system will close. There is still pent up pressure inside the motor that will need a free vent under this condition.

What some people mentioned but I have not seen a single example of is a vacuum regulator as I would be interested in installing one to control the crankcase vacuum, Jegs version shown here ( http://www.jegs.com/p/JEGS/756311/10002/-1 ). I had the idea of installing this on the backside of the valve cover near the cam sprocket, out of the way of the intake/fuel rail hopefully. My question regarding this, would you install a filter on this? It obviously opens up to allow ventilation into the crankcase to limit the vacuum on it, but I'm assuming its not a very big orifice, should one be installed to be safe?

I have yet to need one of those. That would be something that I would wait on until you get your system hooked up to see how it does as it may not need regulation.

Now with a regulated vacuum you should limit the vacuum and hopefully the amount of oil sucked into the exhaust I wanted one more safety that had been brought up but I have seen no examples of one installed. Would a catch can be beneficial in between the valve cover and exhaust check valve?

No, not for our applications

The issue I see here is most catch cans have small hoses (like 3/8s inlets) whereas the standard size for the evac hose is 5/8ths. Would it cause any problems adapting the hose down to run through a catch can? Is a catch can really needed if you are limited the vacuum? Anyone have a link to a good alum (even ebay style) that are not too big even kinda small in diameter? I don't want to have to run 3 ft of extra hose and mount this to the rad support. Just as I was typing this I just had a realization I could run my evac hose across the intake and down the passenger side firewall where I might be able to hide a catch can down on the firewall (I'm running a TU header so room on the firewall on the drivers side is... well, nearly non existent). The check valve could be installed down on that side as well, doesn't matter which side is on as long as its past my WB02 to avoid contamination.

Don;t overthink the setup...it's VERY simple and it works if done properly. The biggest thing to get right is to be sure that the weld in piece is at a 45 deg. angle. No need for catch cans and regulators and whatever else.

I heard it asked but didn't get a good answer, where can you buy black silicone 5/8ths hose for running the evac hose?

Maybe Ebay? I'm actually using hose that Reeves runs and I use on a daily driver which comes from Lowes or Home Depot and it's clear with some type of loose weeve reinforcement. It looks almost exactly like oversized draft line for fountain drinks if you know what I mean. It seems to hold up to the temps and abuse of everyday driving just fine...and I have it routed down the drivers side right by the turbo!

Thanks for any input or any recommendations from the guys who have experience in this department. If you have an evac system, are you happy with it and what would you change?

100% happy. Forgot to mention I also use a Cast TBI valve cover with the oil control cutrain underneath. This setup seems to be the hot ticket on the 8 valve cars but doesn't look as cool as the turbo/shelby covers.

Do you think a setup with all the bits I've listed above be overkill or just right?

Overkill

I'll spend a few bucks to get a good system going if I have to... I know having vacuum on the crankcase should be worth power and better for the motor as well (so I hear) so I'd like to get this done... I want to run higher boost reliably... the oil smell/mess is bothering me.

P.S. Sorry for the long post, I didn't realize I had that much to say

[tryingbe]

Here's what I did to get rid of the oil mess, except now I have a cast valve cover.

http://www.turbo-mopar.com/forums/sh...light=oil+free

[t3rse]

I used heat hose for a long time with no failure, but i am switching to the pvc hose that andy mentioned, which is the same stuff i'm using on my w/a i/c plumbing

[Mike M]

Thanks for the input guys, I really am not to keen on running a PCV system back through the intake. And thanks badandy for cross-examining my entire post I'm glad I've been over-thinking the setup!

I was going to reply again after I said that about a breather system as it will be needed under no load situations (unless your evac system pulls vac at idle, but I guess there are other scenarios as well), I still have a quick question regarding that. Would the breather require a check valve of sorts? Once the evac system is functioning under full throttle and sucking the crankcase down, would an open breather filter eliminate the vacuum effect? It would pull blow-by out I imagine and pull in fresh air but would it pull enough vacuum in the crankcase to have the benefits of better ring seal under high boost? What do you use in your system? I have heard of people modding a breather/filler cap with a rubber seal to act as a check valve, necessary? I haven't decided whether I'll drill/tap my valve cover or use a breather cap yet.

I am aware of the clear hose but I was interested in the black silicone... I mean this is an award winning show car, including Best Sport Compact Engine... I ain't gonna make it ugly! I could use heater hose as a temporary thing if I can't find silicone hose soon enough.

Thanks again guys!

[badandy]

Thanks for the input guys, I really am not to keen on running a PCV system back through the intake. And thanks badandy for cross-examining my entire post I'm glad I've been over-thinking the setup!

Well, I can understand. I just had to mess with it and get some experience with it. Each car I put it on seems to be a little better each time due to placement or sharing of ideas with others.

I was going to reply again after I said that about a breather system as it will be needed under no load situations (unless your evac system pulls vac at idle, but I guess there are other scenarios as well),

My 91 daytona shelby (Whitey) would smoke tremendously if I got on it real good and backed off the throttle. At this time I think I concluded that with the crancase under vacuum and with the intake manifold under vacuum...that oil was being pulled past the turbo seal most likely. My quick fix was to put a free vent filter on the valve cover and it fixed my issues. I ran 24 lbs. boost on that 2.5 motor with 150,000 miles and the car would rip off 13.0's in the heat...and no messy oil residue anywhere...so it must have been doing it's job!

I still have a quick question regarding that. Would the breather require a check valve of sorts? Once the evac system is functioning under full throttle and sucking the crankcase down, would an open breather filter eliminate the vacuum effect?

No, just as long as your breather filter isn't too large. I think the key is to keep the vacuum side and the free vent side roughly the same size. Due to the vacuum being fairly strong the size of the free vent orifice can actually be somewhat of a way to "tune" the setup

It would pull blow-by out I imagine and pull in fresh air but would it pull enough vacuum in the crankcase to have the benefits of better ring seal under high boost? What do you use in your system?

I have the evac on one valve cover nipple and a free vent filter on the other nipple along with the cast TBI valve cover as previously mentioned and pictured by another member

I have heard of people modding a breather/filler cap with a rubber seal to act as a check valve, necessary? I haven't decided whether I'll drill/tap my valve cover or use a breather cap yet.

No check valve neccessary. A breather oil cap would be the easiest thing to do for sure but I don;t care for the looks of them.

I am aware of the clear hose but I was interested in the black silicone... I mean this is an award winning show car, including Best Sport Compact Engine... I ain't gonna make it ugly! I could use heater hose as a temporary thing if I can't find silicone hose soon enough.

Thanks again guys!

If you find the hose let me know where and how much...but the benefits of the clear hose is that you can see that the vent system is working because the hose will dirty somewhat.

Post up some pics of your ride

[Speedeuphoria]

I'm always amazed at this topic. In my findings 50% of people who try it, it doesnt work, the other 50% say it works great.

There has to be something that the people who get it to work are doing different or they are not testing with a gauge to makes sure they are getting vac.

[badandy]

I'm always amazed at this topic. In my findings 50% of people who try it, it doesnt work, the other 50% say it works great.

There has to be something that the people who get it to work are doing different or they are not testing with a gauge to makes sure they are getting vac.

It's all in the exactness of welding in the fitting. It needs to be a certain depth and angle. Mine gets vacuum at idle and when yoou rev it the vacuum increases. I really don't feel I need to test it with a gauge to tell me what I already know (no offense meant there). Like I said...the benefit of the transparent hose is that you can see that the system is doing it's job.

I have 124,000 on a stock bottom end and can run 20 + lbs of boost without blowby oil all over my engine or a bunch of oil accumulating in a catch can that has to be drained...and my oil level stays where it should. I guess I just go on common sense tells me that when setup properly it works.

There has to be a reason why I see this setup on drag cars that don't have the vacuum pump setup. It's proven to work when installed correctly.

[Speedeuphoria]

What do you have for exhaust? any mufflers or cats? and where is the nipple placed?

I'm not saying it doesnt work, I'm just trying to figure out why it only works for some and not for others?

There are 4 people I know that tried this that are knowledgeable(Carl aka DBLTRBL, KeDavis, Wallace on the drag Omni and the R/T, Shadow). One would run 10 sec 1/4 mile if he ever went to a 1/4 mile track(mainly does 1/8 mile). The other runs 9 seconds in the 1/4 mile and the other 2 run 11.5 or faster. All said they got no vac. I'm pretty sure they have enough knowledge to make it work, but it did not work as advertised for them(no vac). Of course there at least 1/2 dozen others that report the same thing. Then there is the 1/2 dozen that say it works great.

I'm just trying to figure out what exactly is the "key"?. Everyone knows about putting the nipple in at an angle, the kits they sell have a notch in the nipple to locate it correctly. Are you using this nipple? or did you make your own?

What is the correct "certain depth and angle"? as others seem not to be able to duplicate it. You say 45deg, and do you have a slash cut for the exit(thats parallel to the main pipe)? how deep is yours? Are the nipples from the kit made wrong?

The things that you mention as proof of it working are not proof IMO. You say that clear hose shows you its working. Well clear hose thats getting exhaust will not stay clear.

Also you say that it was smoking on let off, then you added a breather/vent and it stopped. So did you try with only the breather/vent to see if it was actually the evac working or the vent fixed the issue?

Since I love this topic I will try to dig up all the threads and quotes that I have just to add to discussion. Many different versions and views on PCV.
http://www.turbobuick.com/forums/gen...-pump-how.html
http://www.honda-tech.com/zerothread?id=1199935&page=1
http://www.turbododge.com/forums/f11...case-evac.html
http://www.turbododge.com/forums/f11...vacuation.html

This if from someone that had it work, but did not use a kit:

Distributor hole will be perfect, ideal location.
Vented breather in VC will let vaccuum in
block scavenge before vac is lost up top
thru head's factory vent.

Closer up the better, downline of O2 sensor.

The more the angle it seams like the better it
pull's, the slash cut should be even with angle
in that it has 100% coverage in pipe. I weld
mine 1/8-3/8" inside the pipe, pulls hard enough
you can feel it at idle and nearly squish's silicone
hose when revving motor. Decelling after a 12 second
full pull burp's a puff of smoke out tailpipe at end of
track (doing its job pefectly!).

If you overengineer it and it pulls tooo hard, like raw
clean oil puddles at tailpipe or thru exhaust cutout
simply restrict ID of suction hose, I used a simple
gated water valve to try different openings until
it sucks the bad boosted oil pan fumes out but left
motor oil in bottom of pan.

Actually in that last thread I forgot that my assumption was that the people having issues must not have had a breather/vent. I'm not positive that that is the case but its my opinion that a vent IS needed.

[badandy]

What do you have for exhaust? any mufflers or cats? and where is the nipple placed?

3" Stainless mandrel bent exhaust no cat ATR muffler (FM exhaust kit) The nipple is placed in my mid pipe behind my wideband.

I'm not saying it doesnt work, I'm just trying to figure out why it only works for some and not for others?

I would say too much exhaust backpressure could cause a problem...so could welding the nipple in at the wrong angle....a kinked hose...a bad evac valve...etc. I also believe that location has much to do with it. I know as exhaust gas cools it also slows down...would this create a problem?...here again I don't know?

There are 4 people I know that tried this that are knowledgeable(Carl aka DBLTRBL, KeDavis, Wallace on the drag Omni and the R/T, Shadow). One would run 10 sec 1/4 mile if he ever went to a 1/4 mile track(mainly does 1/8 mile). The other runs 9 seconds in the 1/4 mile and the other 2 run 11.5 or faster. All said they got no vac. I'm pretty sure they have enough knowledge to make it work, but it did not work as advertised for them(no vac). Of course there at least 1/2 dozen others that report the same thing. Then there is the 1/2 dozen that say it works great.

It's just like anything else I suppose...what works for some will not work for others. All I know to say is that it is a very sound principal and is used widely in the drag racing world...it works for them and it works for me. If we are gonna go into who's who and how fast they (if that is supposed to give a topic more credit?) than James Reeves uses the setup...although he does use both nipples in the kit. I'm sure there is more pressure present in his exhaust by comparison to someone like me....so maybe that was your friends problems? maybe one kit was not sufficient for the power level?

I myself am not near as fast as those guys so maybe that would make some people doubt my experiences?...I don't know?...but I've been around about 18 years with these cars so I feel like I know enough to satisfy myself with something like this. If someone wants to jump in their car and come visit me and check it out for themselves than come on we will hang out and drink beer

I'm just trying to figure out what exactly is the "key"?. Everyone knows about putting the nipple in at an angle, the kits they sell have a notch in the nipple to locate it correctly. Are you using this nipple? or did you make your own?

I used the kit supplied one (MOROSO). I don't think we relied so much on the notch as we just made sure it was at the proper angle. it helped tremendously that it was in my mid pipe which is short...thereby you can easily see down inside the pipe for adjustment before you tack it up. I do remember the cut in the nipple being rough and having a bunch of flash aroud it...I remember we cleaned that up...but like I said we didn't use the notch as a locator for the angle and we drilled the hole a little big and welded up the seam. if you use that notch I would think that would reduce the size of the inner diameter of the pipe...which could restrict your suction.

What is the correct "certain depth and angle"? as others seem not to be able to duplicate it. You say 45deg, and do you have a slash cut for the exit(thats parallel to the main pipe)? how deep is yours? Are the nipples from the kit made wrong?

What the instructions specified for the most part...we may have gone a touch deeper as we didn't rely on the notch. We made the hole a little big so we could adjust the depth. What the final depth was I'm not sure.

The things that you mention as proof of it working are not proof IMO. You say that clear hose shows you its working. Well clear hose thats getting exhaust will not stay clear.

Well, I respect your opinion but I have no idea what else you would want or need to be satisfied...nor am I trying to satisfy you or sell the idea to anyone that is against it. I'm really not trying to disprove anyone elses findings nor do I doubt them that it didn't work for them...like I said...something just wasn't right

...and not being harsh but clear hose that is seeing exhaust? why would it ever see exhaust?...I can see crankcase residue (oil mist)

Also you say that it was smoking on let off, then you added a breather/vent and it stopped. So did you try with only the breather/vent to see if it was actually the evac working or the vent fixed the issue?

I, like everyone else, have ran around with only a breather filter on my valve cover for years. The major proof I have of the kits working for me is no dipstick popping out or oil residue all over the place...along with the other things that are not proof in your opinion...it just seems to be a common sense conclusion that it's working. If before I have problems and then I don't afterwards....and I can pull the hose off at idle and feel vacuum than that satisfies me
-

Since I love this topic I will try to dig up all the threads and quotes that I have just to add to discussion. Many different versions and views on PCV.
http://www.turbobuick.com/forums/gen...-pump-how.html
http://www.honda-tech.com/zerothread?id=1199935&page=1
http://www.turbododge.com/forums/f11...case-evac.html
http://www.turbododge.com/forums/f11...vacuation.html

This if from someone that had it work, but did not use a kit:


Actually in that last thread I forgot that my assumption was that the people having issues must not have had a breather/vent. I'm not positive that that is the case but its my opinion that a vent IS needed.

YUP! that's my experience...

I think of it like a vacuum cleaner...there is no way it can pull in suction if it doesn't have exhaust or an intake...and being as a motor is sealed up than where is the intake?

[badandy]

Another thought...

These kits are normally used on headers instead of full exhaust systems...with that thought in mind there is no restriction downstream.

Onto my theory...

It seems to make sense to me that the more power you make the more this system will not work if you run a full exhaust...for example...let's say I make 250 hp and it works for me but someone else with my same exhaust system is running 450 hp...common sense would tell me that they have more exhaust backpressure which would keep the evac setup from working as well...hence why some people will actually use two kits.

In other words setup of the nipple being proper and everything else being correct may not be the be all end all of if it works or not...power level and exhaust setup most likely is the deciding factor.

[t3rse]

exhaust diameter is what matters: a 4" pipe is going to have slower moving gasses than a 2.5" at the same exhaust throughput...therefore the 2.5" will pull more vacuum. Look at high end collectors and the way they taper at the end to increase velocity.


The reason they often don't work for people is because people install them wrong or put the nipples in bad locations...more or less to reiterate what was stated....

[puppet]

I was one that tried this with mixed results.
I located the nipple in the first 12" of the 3" DP. Without a check valve installed you could feel the pulsing of the exhaust up and down the hose. With the check valve it pulled vacuum but not enough (WOT). I do have the big DynoMax right where the CAT used to be. I'm pretty sure this is why my results were mixed ... even though it's a straight through design type muffler. Worst thing that happened on my set-up was a small seepage around the rear cam cap @25psi (exhaust evac w/check valve) <---- told me that it wasn't working out right.

These types of evac only draw 3-5" (max) on an ideal set-up anyway. Vacuum pumps have a tough time keeping up with big boost apps and they draw even more HG. Thinking that the problem here is the line ID restrictions once you get to a certain boost level. I've always tried to get the pressure out first and as fast as possible.

I'll get a chance to rework the nipple and/or muffler location in the future to satisfy my desire to get something for free. Maybe it'll work better. Right now I've gone back to the "hose to free air" method. TBI cover with (2) individual 3/4" ID hoses (silicon lined "Dayton") right to atmosphere has worked best for me. Reeve twin hose set-up sounds interesting. Allow a lot of air to move quick while inducing a little vaacuum on the oil pan.

[black86glhs]

What some people mentioned but I have not seen a single example of is a vacuum regulator as I would be interested in installing one to control the crankcase vacuum, Jegs version shown here ( http://www.jegs.com/p/JEGS/756311/10002/-1 ). I had the idea of installing this on the backside of the valve cover near the cam sprocket, out of the way of the intake/fuel rail hopefully. My question regarding this, would you install a filter on this? It obviously opens up to allow ventilation into the crankcase to limit the vacuum on it, but I'm assuming its not a very big orifice, should one be installed to be safe?

I drilled a hole and used a 5/8" heater hose fitting for fresh air intake on one of my VCs. It was located right behind cyl #1 cam lobes. I made a shield that sits between the cam and new fitting. On the stock location I ran 5/8 emissions hose to a GM 3.8 V6 PCV valve. This dropped down to a 3/8 hose that I ran to the fitting on the front of my 2 piece intake.
On the new fitting, I ran 5/8 hose back to a breather filter that sits near my fuel lines. After making some restrictors to go inline on both the air intake and the pcv setup, it seems to be working quite well. The breather element isn't dripping with oil anymore. Just an idea for others.

[Shadow]

exhaust diameter is what matters: a 4" pipe is going to have slower moving gasses than a 2.5" at the same exhaust throughput...therefore the 2.5" will pull more vacuum. Look at high end collectors and the way they taper at the end to increase velocity.

I will agree that exhaust velocity is the key. I had 2 of these spouts in my 68 383 Charger and it worked flawlesly! I then installed 1 in my 87 Daytona (about 12 years ago) and @ 20 psi (that's what I ran back then) it seemed to work great. So this was what I relyed on for my current Charger. Around 30 psi I started to notice the dipstick coming out and other signs that my CC preasure was to high (oil was pushing up my distributor shaft and oiling my pick-up). I decided to test it. Put a nipple on an oil cap and hooked up a gauge, and ya, when I put my thumb on the end of the hose I could feel vac at idle. Went for a ride and at 30 psi I had 2-3psi in my mtr. Disconected it and I had about 1psi. Spent a week trying every angle and every depth and came to the conclution that my 3' exhaust(at the time) + the fact that there's a turbine wheel killing the exhaust velocity I had with my N/A BB Charger, was not allowing enough exhaust velocity for the system to work right. I then punched 2 5/8 holes in my valve cover and ran 2 5/8 hoses to a filter box and now at 37 psi I have NO boost preasure in my mtr!To each his own!

[Russ Jerome]

http://hometown.aol.com/russjerome/i...vdownpipe1.jpg

Research the Bernilli principle, help picture whats
going on. The Ford A.I.R. valve above works great.

[Ondonti]

Works good for me. Stops oil from squirting out all my seals and it squirts into the exhaust instead


Not having vacuum is not the same thing as something not working.

If you are pushing a lot of blowbye, you need to have adequate evacuation to remove it all. If you dont have enough (in the case of shadow) then its gonna build pressure.

The problem I have had is that the 3.0 has tiny drainback holes so you cant draw lots of gases through the valve covers. I run Two valves in my downpipe. Right now one tee's into both valve covers, and the other goes to the top front of the oilpan.

[puppet]

Not having vacuum is not the same thing as something not working.

Unless that something is supposed to induce a vacuum. If my vacuum cleaner doesn't produce a vacuum that's the same thing as it not working.

[puppet]

Does the interior of the exhaust pipe have a boundary layer too? Maybe Andy has the right idea of pushing the nipple down further to get into the faster stream?