whos running an EVAC setup??

[Juggy]

shout out to all those with evac setups!!!

me and my buddy in town are both running evac's, off of the valve cover with 1 way check valve to the exhaust, to take care of any possible crank case pressure (altho i still seem to be getting some?!??!)

anywho, both cars smoke pretty bad at WOT. white cloudy smoke. my motor is fairly fresh with only a few thousand K, and his was just built 1000k ago if that!!!

anywho im runnin a turbo valve cover, removed the baffle, and am running the TBI curtain, he was doing the same thing, but told me 2night that he swapped back to the stock turbo baffle, and it doesnt seem to smoke as bad.

both of us are experience some oil in the exhaust as well?? is this normal?? the oil is coming from the check valve no doubt!

any knowledge and ifo on this is greatly appreciated! i know theres a few of yous running this type of setup, just would like to know whats goin on, on your end and how its all setuP!

i dumped mine at the end of the downpipe, he dumped his even further back, somewhere after the cat would usually go :eyebrows:

[Speedeuphoria]

are either of you using a breather/vent on the VC?

[inmyshadow]

I was wondering the samething.

My friend hooked up his PCV to his exhaust. He was a few towns over when he noticed no oil pressure at idle. He made a quick trip to the parts to find the car was sucking so hard at idle. I put on a vented oil cap to solve the problem.

I'm getting ready hook the PCV to the exhaust too. But I drilled another hole by the cam gear and run a PCV filter.


are either of you using a breather/vent on the VC?

[2.2turboscotty]

Cory, i have done the exhaust evac setup in my Scamp because i was running into problems of smoking after a hard run. i had just a K&N filter on the VC and i guessed it was not enought when i upped the boost psi. it was fine at 14-16psi but not at 20+ or so, i went the same way as you with the one way check valve in the downpipe with heater hose running off the VC nipple. i have not had any issues yet but i am still testing and tuning the car before i go to the track. i do remember reading something about using an extra filter on the VC like James said to do over at BM or on here, can't remember which. i haven't noticed anything wrong with mine but i may go the extra filter route if i do.

[shelbyplaya]

I'm running a set up like that on my hybrid 16v 2.5l. I connected it to the exhaust jsut after the DP. The issue I'm having with mine is that I think it's sucking to much cuz I actuly have oil in my exhaust.

Truth be told I think it's a combo of 2 issues. Lack of oil flow to the head/to much oil in the head and to much suction from the e-vac, so it's sucking in raw oil into the exhaust and smoking real bad in higher revs.


Any way to test how much vac it's producing at differnt revs?

[2.2turboscotty]

i'm sure that there is a way to check what kind of vac is in the exhaust but i guess if you have a vac gauge and used a long piece of vac line hooked at the valve and drove the car looking at the gauge that would tell you. i had a simular setup on a 440 Roadrunner but with a different oil cap and breather and it worked. i have not had any issues yet with mine but like i said i'm still in the testing stages with this car, it's not really driven on the street. my problems with smoking was after i was running the car really hard and then it came back down to idle it would smoke untill i cut the car off. never saw any smoke while in boost but hard to see when trying to keep the car under control, lots of wheel spin. i may do some runs today while bringing up the boost even more in it and see what happens.

[Juggy]

I'm running a set up like that on my hybrid 16v 2.5l. I connected it to the exhaust jsut after the DP. The issue I'm having with mine is that I think it's sucking to much cuz I actuly have oil in my exhaust.

Truth be told I think it's a combo of 2 issues. Lack of oil flow to the head/to much oil in the head and to much suction from the e-vac, so it's sucking in raw oil into the exhaust and smoking real bad in higher revs.


Any way to test how much vac it's producing at differnt revs?


YES, this seems like its exactly what is happening here, boths cars have exhaust SOAKED in oil from the check valve back!

neither car is running a filter!!! I thought the filter would just allow a place for the oil to escape b4 it made its way out the evac.
im guessing this is where my TBI valve cover comes into play? use 1 nipple for the EVAC and the other nipple for a small air filter.

Ive never experienced the blow by problem driving normal under vac, it seems to start around 15-16 psi boost.

im just having a hard time tryin to figure out why its suckin all that oil out so bad, when that TBI cam curtain does a really awesome job of keeping that oil under control

[2.2turboscotty]

how about adding a catchcan in line do you think that would help? that is another thing i read about using with the exhaust setup.

[Juggy]

yes that has come across my mind as well, then the filter could be put on the top of the catch can

[shelbyplaya]

I think with these guyes problum a catch can and possably a restrictor might help as well.

My issue it looks like my turbo blew up when i lay into it :(

I would fill a catch can in no time at all.

[1966 dart wagon]

i had a catch can on my car, a homemade one made from an water trap on a air compressor, i though it restricted to much, plus then i blew a oil pan gasket i believe. so i changed it to the 'gus' style, hose with steel wool in it, good to go, im also running a pcv valve on my oil cap too, into a bottle

[Ondonti]

The kits come with an oil/air separator for a reason (which nobody in the import/turbo world seems to use)

I use one on my front cover but not my rear cover (haven't taken the time to install one there).

3.0's have horrible problems with oil drainback. I filled the valley between my cylinder banks with oil when I ran 2 valves (one for each cover) because the oil wouldnt drain. I stopped using one of the valves and tee'd one valve into both covers and it stopped filling the valley with oil. I am running both valves again, but one routes to the top of my oil pan. it burns lots of oil now that I turned the boost up, so I need to add an oil/air seperator on that fitting I think and maybe a baffle over the hole in the pan.

Only 3 drainback holes in each side of the block and they are much smaller in diameter then a dime.

The reason why I suggest an oil/air seperator, is that you will waste a LOT of oil if you just throw it into a catch can.

[tryingbe]

neither car is running a filter!!! I thought the filter would just allow a place for the oil to escape b4 it made its way out the evac.



If the oil fume couldn't get out from the exhaust, it needs another exit. The filter would provide that exit.


I don't have smoking problem from my PCV setup.
http://www.turbo-mopar.com/forums/showthread.php?t=23885

[Ondonti]

Why would you have a vent before the exhaust. That would ruin the whole point of the system. It would suck air from the filter instead of from your motor.

[tryingbe]

I suggest you read.

http://en.wikipedia.org/wiki/PCV_valve

[Ondonti]

I suggest you read.

http://en.wikipedia.org/wiki/PCV_valve

He is running an EVAC system not PCV anymore. Try googling that.

If you dont understand how a filter would make the EVAC worthless, dont give advice.

[tryingbe]

His EVAC is running so well that he's blowing smoke.

FYI, filter would not go between the engine and the EVAC system. You'd have to use a TBI valve cover to get the two nipples, one goes to the EVAC system, the other goes to the filter.

[Speedeuphoria]

All I know is that people say it doesnt work and they get smoke and people say it works and get smoke, pick one

[Juggy]

His EVAC is running so well that he's blowing smoke.

FYI, filter would not go between the engine and the EVAC system. You'd have to use a TBI valve cover to get the two nipples, one goes to the EVAC system, the other goes to the filter.


ok, that actually makes some sence there! btw that PCV link was good info!

so my car is scavenging the crank case pressure so well that its actually sucking out oil along with it??
the filter thing is starting to make more sense now, the evac would still work, the filter just allowing as a vent, which the evac would be sucking air through the filter and then back out the evac with the rest of the crankcase pressure???

I do have a TBI valve cover, not the prettiest looking thing, but will definately have to check it out and see if that works.

my friend went a different route. he hacked up a valve cover, to add 2 fiilters, one in place of the oil cap, and the other at the stock turbo nipple, and he is going to T them in line then out to the 1 way check valve. I thought he went a little extreme but hey whatever LOL its his mess

[Tony Hanna]

If somebody could "T" into their EVAC line and run a vacuum gauge inside the car, it would be a big help. If all this smoking is caused by an excess of vacuum, then I have an idea that might provide a solution.

Tony

[Juggy]

If somebody could "T" into their EVAC line and run a vacuum gauge inside the car, it would be a big help. If all this smoking is caused by an excess of vacuum, then I have an idea that might provide a solution.

Tony


I got a spare vac/boost guage, that i could figure out some way of T ing it into the evac

[Speedeuphoria]

I got a spare vac/boost guage, that i could figure out some way of T ing it into the evac

just take your dipstick out, hook a vac line from it to the vac/boost gauge and see what it says

[Tony Hanna]

Sure, off the dipstick tube should work fine.

If you do find out that the smoking is happening when the crankcase is under higher vacuum, the solution should be as simple as everybody's favorite G-valve.

Simply cut the line going from your check valve to your valve cover and install a "T". Attach the G-valve to the open leg of the "T" and move the ball and spring in the valve so that it will open under vacuum (ball at the cap end and spring below it).

With the G-valve installed like this, you should be able to set the maximum vacuum your crankcase will see (tightening the valve would increase max vacuum and loosening would drop it).

The theory is that once there is enough vacuum in the system to overcome the spring in the G-valve, it will start drawing in fresh air from the valve instead of increasing the vacuum on the crankcase. Basically it would work exactly like a G-valve on a map sensor line does to regulate pressure and prevent overboost except that in this case we're regulating vacuum.

The only possible problem I can see with this is that the G-valves we normally use for other stuff might be too small to handle the volume. They are available in sizes up to 3/4" NPT though so if one of the common size valves won't do it, I feel pretty confident that a larger one would.:)

Tony

[WickedShelby88]

Hehe.. and if that isn't big enough I'm sure I could tool something even bigger on the manual lathe out of brass.

[Tony Hanna]

Hehe.. and if that isn't big enough I'm sure I could tool something even bigger on the manual lathe out of brass.

Sure.:thumb:
And for those without access to a lathe, I bet something big enough could be put together reasonably easily out of a ball bearing, spring, and some brass fittings from the local hardware store.:) Maybe a large brass "T" with the ball and spring inside, hose barbs on the side and one end, and a bolt threaded into the other end to set the preload on the spring.:)

Another possible way to approach the problem would be to use a vacuum switch to power some sort of high volume 12v solenoid. When vacuum increases, the switch closes, opens the solenoid, and breaks the vacuum. When the vacuum falls back to a reasonable level, the switch opens, closes the solenoid, and allows the vacuum to increase again. I'm betting a setup like that would "flutter" to hold the vacuum near the level that the switch is set for.:nod:

[Ondonti]

Use oil air seperators!

its pulling oil/air mist, not actual oil.

Or run a catch can between. Putting a filter on ruins the point of the evac. If you put a filter on then just run open breathers to a catch can. No point using exhaust evac if you create a leak.

A filter wont stop oil air mist from going into the exhaust, and that is your problem.

If Shadow can get away with two huge breather holes in his valve cover and his motor doesnt trap oil in the head from blowby gasses passing out the valve cover, then an exhaust evac wont either. The evac can only pull as much air as leaks past the rings. Once it creates vacuum that doesnt mean it sucks oil. It sucks oil mist air just like your PCV system does :(

[Speedeuphoria]

If Shadow can get away with two huge breather holes in his valve cover and his motor doesnt trap oil in the head from blowby gasses passing out the valve cover, then an exhaust evac wont either. The evac can only pull as much air as leaks past the rings. Once it creates vacuum that doesnt mean it sucks oil. It sucks oil mist air just like your PCV system does :(

This doesnt make sense to me.

[Ondonti]

This doesnt make sense to me.

If his 2" open breathers vent enough blow bye from a 500hp engine then 1 evac hose on a 250whp motor is NOT going to pull enough air to make oil puddle in the heads.

Just because an evac can pull vacuum on your motor doesnt mean its moving a lot of CFM's. That might just mean that your motor doesnt have much blowbye.


Just because you suck on a barb located on top of an engine that doesnt mean you are going to suck up oil.

You are sucking up oil vapors. Those oil vapors are normally burned in the cylinder by PCV systems so it comes out pretty dang clean. When you dump those same vapors into the exhaust, they dont burn all the way and they smoke.

Exhaust evac WILL create smoke in your exhaust if you dont have very good oil air separators before the downpipe.

I just took apart my lower vent and it was sucking oil from the top of my oil pan but thats only because I have way to much blow bye from a crap motor.

[Ondonti]

Matt Monett's 3000gt ran 8.81 with 950whp on tap and 20psi in the slicks.
Should be around 1150awhp right now.

He has great success with only two valves.

BTW, these are quite different then the moroso ones I use. THese go much deeper it looks like, and no check valve (though I dont think a check valve does anything but decrease the amount of vacuum).


The valve covers are vented to the crank case vent system in the Exhaust.

2 of these in fact


Dynatech 85-100950 - Dynatech O2 Sensor/ Pan E-Vac Kit - JEGS (http://www.jegs.com/i/Dynatech/329/85-100950/10002/-1)

[Tony Hanna]

According to http://www.streetperformance.com/part/dynatech/positive-crankcase-ventilation/211838-85-100950.html those Dynatech kits are intended to be used with a check valve, it's just not included.
I'd be a little concerned about running without one. It might be nothing, but I can think of some instances where the exhaust could become pressurized (backfires, melted cat, run over something and crush the pipe, etc.). Not sure if any of those instances would develop enough pressure to harm seals and gaskets, but I don't know if I'd want to take the chance either. I mean it's just a check valve, so really it's only going to limit the vacuum to the point it takes to reach the cracking pressure of the valve. I don't have one here to test, but I can't imagine it would be much.

[Ondonti]

I dont have clamps on all my hoses so I think they would blow off :P
Anyone running a CAT with this setup and placing the valve before the cat....better have a dang good catch can.