Crankcase evac tuning/sensor question

[Nostang 96z]

I am in the process of finishing my solid roller 383 build and I am looking into crankcase evac systems that tie into the header collector. I am going with a FAST XFI setup and need to know if this type of setup will affect the wideband o2 sensor? Any help/info/experiences are greatly appreciated.

Thanks,

Matt

[Fastbird]

I am in the process of finishing my solid roller 383 build and I am looking into crankcase evac systems that tie into the header collector. I am going with a FAST XFI setup and need to know if this type of setup will affect the wideband o2 sensor? Any help/info/experiences are greatly appreciated.

Thanks,

Matt

I don't think that would work. You need to evac the crankcase to a vacuum source, the exhaust won't work for that. Pipe it to the intake tract.

And yes, that would mess with your wide band. It's fresh O2 being introduced to the stream, and easily could contain oil particles that will drastically affect the readings.

[BLOWNDFIZ]

I am in the process of finishing my solid roller 383 build and I am looking into crankcase evac systems that tie into the header collector. I am going with a FAST XFI setup and need to know if this type of setup will affect the wideband o2 sensor? Any help/info/experiences are greatly appreciated.

Thanks,

Matt


I don't think that would work. You need to evac the crankcase to a vacuum source, the exhaust won't work for that. Pipe it to the intake tract.

And yes, that would mess with your wide band. It's fresh O2 being introduced to the stream, and easily could contain oil particles that will drastically affect the readings.

I agree with Fastbird. The crankcase evac system you are referring to is designed to be used 1/4 mile at a time where the vacuum created by the exhaust helps to evacuate the crankcase pressure. Since you will not be WOT 99% of the time your exhaust will not create enough "pull" to make the system effective.

I'm also not a fan of plumbing it back into the intake tract. Personally I didn't want the possibility of any oil being pulled back into the intake. When I ran the vortech with the factory PCM the vent was ran back into the intake and when I pulled my inlet elbow off there was oil residue on the throttle body (just a slight film). Since then I have ran a -10 line from the valve cover to a catch can that I mounted below the battery tray. It's the plastic Summit catch can with a filter on top and drain on the bottom. It works very, very well.

[Nostang 96z]

Thanks for the replies! Keep them coming. The main concern is the wideband sensor as the tube for the exhaust will be in close proximatey of the wideband. I was talking with Lloyd Elliot and he was saying that these systems work great on carb cars but was unsure of the effects they could have on the wideband. These system do work at different RPM from my research. Check out this video:

YouTube - Crankcase Evacuation Proof!

I will either run the crankcase evac if there are no effects on the wideband or one breather in each valve cover.

[BLOWNDFIZ]

I will either run the crankcase evac if there are no effects on the wideband or one breather in each valve cover.

I wouldn't risk damaging the O2. I know the sensor for my DFI is the NTK version which is over $300 to replace. If it were just the standard bosch I'd try it but I'm assuming XFI uses the better sensor as well.

I ran a breather in each valve cover, but I hated the oil residue on the valve covers that I seemed to always be cleaning off. It does work though.

[paul95z]

I run a vacuum pump set up. It was basically a bolt on install. It mounts on the driver side so the factory accesory bracket would work.
http://i200.photobucket.com/albums/aa185/Paul95z28/DSC00469.jpg

Also, Thunder Racing sells an electric kit. It doesnt pull as much vacuum as a belt driven but it does more than the check valve in the header deal. I tried to find a link to it on thier site, but failed miserably.

[Nostang 96z]

I run a vacuum pump set up. It was basically a bolt on install. It mounts on the driver side so the factory accesory bracket would work.
http://i200.photobucket.com/albums/aa185/Paul95z28/DSC00469.jpg

Also, Thunder Racing sells an electric kit. It doesnt pull as much vacuum as a belt driven but it does more than the check valve in the header deal. I tried to find a link to it on thier site, but failed miserably.


What vacuum pump is that and how much did it run you? Also, where did you get it? I ran an electric vaccum pump on my last 355 combo and it worked OK but I did not see a benefit over a breather setup. I am going to be running a motor plate and I only have an alternator and no opti so I should have some room.

Thanks,

Matt

[Fastbird]

I'm also not a fan of plumbing it back into the intake tract. Personally I didn't want the possibility of any oil being pulled back into the intake. When I ran the vortech with the factory PCM the vent was ran back into the intake and when I pulled my inlet elbow off there was oil residue on the throttle body (just a slight film). Since then I have ran a -10 line from the valve cover to a catch can that I mounted below the battery tray. It's the plastic Summit catch can with a filter on top and drain on the bottom. It works very, very well.


Simple fix for that. Catch Can. LS1 guys are VERY familiar with these.

[BLOWNDFIZ]

I'm also not a fan of plumbing it back into the intake tract. Personally I didn't want the possibility of any oil being pulled back into the intake. When I ran the vortech with the factory PCM the vent was ran back into the intake and when I pulled my inlet elbow off there was oil residue on the throttle body (just a slight film). Since then I have ran a -10 line from the valve cover to a catch can that I mounted below the battery tray. It's the plastic Summit catch can with a filter on top and drain on the bottom. It works very, very well.


Simple fix for that. Catch Can. LS1 guys are VERY familiar with these.

Yes sir, it works great! I'll see if I can get some pics in case anyone is interested in seeing it.

[paul95z]

PM sent Nostang. They arent a site vendor, dont wanna break any rules.

[Nostang 96z]

Oh, another thing I gorgot to mention. I do not think my cam will pull enough vacuum to have an effective draw for a PCV system (259 267 @.050 .672 lift and 108 lsa installed on a 104). I do not like the idea of drwing oil back into the intake tract myself.

[Fire67]

To the O.P.
I am running a crankcase evac on my car. It pulls vacum throughout the entire rpm range. Including idle. Dont get the Mr Gasket kit, as you need the tubes with the cut in them like the ones from moroso. If installed correctly they will work.

The only thing I did as far as my WB O2 was to put the tubes and checkvalves downstream of the 02 sensor. With the FAST system, I just put the sensor in one of my collectors, and the tubes about 8" past the 02 bungs in the pipe that joins to each header. Works great as long as you dont go too far back with the tubes.

Almost forgot... These do not work very well with mufflers. They work good with my straight through Dynomax bullet, but anything less than a 'straight through' muffler will introduce backpressure. Backpressure will slow the velocity enough to stop the venturi effect from creating a vacuum.

[lt170chevelle]

either run a catchcan inline or just simply put the sensor in front of the tube for the evac...or better yet...both.. crankcase evac systems do work great.. but then again a belt pump would be best

[jakesz28]

I peronal think the header evac system is marginal at best. I bought one for my car but never got around to putting it on because I plan to put exhaust back on the car and do a little street driving. Running a pcv into the intake is not a choice for any cars starting to make a little power because blowbye is going to happen some. A tight n/a combo you might get by but any type of power adder is going to need a little more ring gap.

I would get an electric or mechanical vacuum pump so you know it will do what is needed.

[The SRZ]

To the O.P.
I am running a crankcase evac on my car. It pulls vacum throughout the entire rpm range. Including idle. Dont get the Mr Gasket kit, as you need the tubes with the cut in them like the ones from moroso. If installed correctly they will work.

The only thing I did as far as my WB O2 was to put the tubes and checkvalves downstream of the 02 sensor. With the FAST system, I just put the sensor in one of my collectors, and the tubes about 8" past the 02 bungs in the pipe that joins to each header. Works great as long as you dont go too far back with the tubes.

Almost forgot... These do not work very well with mufflers. They work good with my straight through Dynomax bullet, but anything less than a 'straight through' muffler will introduce backpressure. Backpressure will slow the velocity enough to stop the venturi effect from creating a vacuum.

I run a 40 series Flowmaster muffler of the 4" variety w/ my evac and it pulls vacuum. I guess it just depends on the vehicle. The catch cans I ran prior rarely collected anything if anything at all so I wasn't sure they worked or not. If I ran breathers I'd get oil mist in the bay but why that same stuff wouldn't collect in my morosso catch cans I have no clue.

[Fire67]

I run a 40 series Flowmaster muffler of the 4" variety w/ my evac and it pulls vacuum. I guess it just depends on the vehicle. The catch cans I ran prior rarely collected anything if anything at all so I wasn't sure they worked or not. If I ran breathers I'd get oil mist in the bay but why that same stuff wouldn't collect in my morosso catch cans I have no clue.

My bullet is a 4" as well. I had a 4" mufflex catback with a Spintech muffler at one point. That did not pull vacuum at idle at all. Not sure about higher rpm, as my check at idle scared me enough to go another route.

[Nostang 96z]

Thanks for the replies everyone. I went ahead and got a GZ crankcase vaccum pump kit for my setup.

[Fire67]

Wow good job. Go from the cheapest "it works" setup to the all out expensive gauranteed to work setup!

[Nostang 96z]

Wow good job. Go from the cheapest "it works" setup to the all out expensive gauranteed to work setup!

I try to save money where I can but I never skimp on parts that are needed!

[jakesz28]

Your going to be glad you got the pump.

[Z28pr0jekt]

Thanks for the replies everyone. I went ahead and got a GZ crankcase vaccum pump kit for my setup.

idk if i missed it throughout the thread but do you have a link to this?

[The SRZ]

idk if i missed it throughout the thread but do you have a link to this?
http://www.gzmotorsports.com/vacuum-pump-guide.html

I'd like to know how you guys mount these things w/ Prochargers. Are these being mounted on the passenger side and removing the AC or something? I've only seen this on a NA car once on the DS of the bay.

[Z28pr0jekt]

http://www.gzmotorsports.com/vacuum-pump-guide.html

I'd like to know how you guys mount these things w/ Prochargers. Are these being mounted on the passenger side and removing the AC or something? I've only seen this on a NA car once on the DS of the bay.

holy shit those are expensive, nevermind haha

[Fire67]

It would have to go on the passenger side, With some sort of custom mounting. Would work rather well in an application that uses a low mount altenator on the Pass side.

Nostang 96z you need to make sure that you get some sort of vacum control setup so that you do not pull too much vacum in the crankcase.

[paul95z]

I have one of thier kits. They come with an adjustable vacuum control that mounts in the valve cover.