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davec73
08-29-2013, 11:16 PM
I am thinking about removing my pcv system and installing crank case breathers on the valve covers. I have an oil catch system now and it catches some of the oil from the crank case but my motor still blows oil out of the oil cap (aftermarket not completely sealed) and the dipstick tube. I have also noticed I am still getting some oil in the supercharger and IC tubes. Is it a good ideal to do this and how will affect the way my car runs? I don't car about emmisions or a little oil smell from the breathers and I know they will fit. This will eliminate a lot of vacuum line for me and if it wont hurt anything performance or dependability wise I think it would be the way for me to go but I havnt seen a lot of guys do this so that's why I am asking.

KMT
08-29-2013, 11:30 PM
I have also noticed I am still getting some oil in the supercharger and IC tubes. .

Seems to be a normal...

Any idea why you'd be tossing oil elsewhere, tho? That doesn't sound normal, and it might be worthwhile to understand why, rather than just venting via breathers, I think.

I'd also think the reason you don't see breathers in use, so much, is because blowing oil out like that isn't a common situation...? I'd try to find out why the crankcase is being over-pressurized (?) and fix that instead of just accommodating what may be a mechanical issue.

davec73
08-29-2013, 11:38 PM
Seems to be a normal...

Any idea why you'd be tossing oil elsewhere, tho? That doesn't sound normal, and it might be worthwhile to understand why, rather than just venting via breathers, I think.

I'd also think the reason you don't see breathers in use, so much, is because blowing oil out like that isn't a common situation...? I'd try to find out why the crankcase is being over-pressurized (?) and fix that instead of just accommodating what may be a mechanical issue.

Its a new motor with 18 + psi of boost could an aftermarket pcv cause it to do this?

KMT
08-29-2013, 11:42 PM
New as in not broken in and the rings haven't seated yet?

I'm not sure all PCVs are created equal. If you can blow thru yours easily, it's not seating under boost at all. I went through 4 before I found one (motor craft black plastic) that would seat at all...be sure to test at an angle similar to how it sits on the valve cover...).

davec73
08-29-2013, 11:54 PM
New as in not broken in and the rings haven't seated yet?

I'm not sure all PCVs are created equal. If you can blow thru yours easily, it's not seating under boost at all. I went through 4 before I found one (motor craft black plastic) that would seat at all...be sure to test at an angle similar to how it sits on the valve cover...).
Motor has around 700 miles on it now. It seems to be leveling off to where it isn't blowing it out of the dipstick and oil cap as bad but it will still do it under high boost pressure. I havnt hammered on it too much because I have been driving it on the 93 tune without methanol. Back to my original question though what would it hurt to vent straight at the valve cover through breathers and remove the pcv system all together? I am just trying to simplify things a bit and let my motor breath better to free up power and prevent the supercharger from getting oil in it.

KMT
08-30-2013, 12:01 AM
Back to my original question though what would it hurt to ven straight at the breather and remove thepcv system all together?

Race engines do it all the time...

BLOWN38
08-30-2013, 02:30 AM
Your fuel trims may be a little off after you put the breathers on , but it shouldn't hurt anything. Be ready for an oily mess, but I guess you already have that.

What I like to do is get the biggest ID fittings you can to put in the valve covers and route both cover outlets to the inlet of the blower that way you get a vacuum in the lines to help evacuate the crankcase. But you need catch cans on both covers so you don't get oil in the intake. Which the oil in the intake is probably coming from the driver side line that you don't have the catch can on.

dthompson
08-30-2013, 06:53 AM
are you using the stock valve covers?

davec73
08-30-2013, 08:20 AM
Your fuel trims may be a little off after you put the breathers on , but it shouldn't hurt anything. Be ready for an oily mess, but I guess you already have that.

What I like to do is get the biggest ID fittings you can to put in the valve covers and route both cover outlets to the inlet of the blower that way you get a vacuum in the lines to help evacuate the crankcase. But you need catch cans on both covers so you don't get oil in the intake. Which the oil in the intake is probably coming from the driver side line that you don't have the catch can on.

There is little to no oil coming out of the driver side into the intake, the intake tube and inlet plenum are clean up to the point where the vacuum line comes into the back. All or most of the oil (which isn't a lot, a little oil makes a big mess lol) is coming from the passenger side through the pcv valve vacuum line portion. I did like you said and increased the size of the fittings and vacuum lines to the catch can and it helped some but under heavy boos it still spray a little oil out of the valve cover and dipstick tube. I was just thinking if I got rid of it all together it would free up a bunch of space and remove a part of the system that has a huge potential for vacuum leaks.

Jacob_Royer
08-30-2013, 08:56 AM
Same problem here new motor oil blows out the dipstick tube under high boost!

820
08-30-2013, 09:08 AM
What systems do the turbo guys use. maybe that could be one answer. afterall boost is boost wether turbo or blower.

Wzenheimer
08-30-2013, 09:18 AM
What systems do the turbo guys use. maybe that could be one answer. afterall boost is boost wether turbo or blower.

On the old blue 95 "Merry Christmas" Turbo car I used to have I just had breathers in the valve covers. I had to wrap them with wrist sweat bands and cut a hole in a tuna can so as to fit underneath of them to catch the oil when racing. I had plans to run a vacuum evacuation system through a catch can but that car was sold. I was trying to find a picture of the setup, but I can't find one.

** edit - I guess I will also add that that car made 28psi. The oil never came out through the dipstick and that motor only had 1500 miles on it.

820
08-30-2013, 09:58 AM
Tuna can, there you go.

DrFishbone
08-30-2013, 10:24 AM
New as in not broken in and the rings haven't seated yet?


You know, that is a good thought I think...

*Warning, hypothesis below - may be totally wrong....*

I wonder if the ring-seating break-in procedure doesn't have something to do with these PCV-like problems, when the PCV checks out okay. Also, I would imagine, the type/material of rings you use.

Venting the pressure will be a metered-air loss, no matter how you delete it, which is why Chris mentioned the fuel trims being a little off. If you have a QH and do your own tuning, and check it every so often, in my mind, it would be okay. However, I don't know how much air we are talking....if you go from less blow-by to more blow-by, your AFR would get richer (not sure how much). If you go from more blow-by to less, your AFR would go leaner. For your guys case, where you have new engines, which possibly may not have rings fully seated, perhaps you would be putting yourself at risk - when the rings fully seat.

One of the SC engine builders around here could comment with some intelligence....

David Neibert
08-30-2013, 02:20 PM
Dave,

Please double check your vacuum hose plumbing and make sure that the hose which connects to the PCV valve on the passenger side valve cover and the fuel vapor canister purge solenoid is attached to the Inlet plenum (that only sees vacuum) and not the return plenum that sees vacuum and boost.

You should also check your PCV valve to insure it is allowing air to travel out of the motor, but not back in. It's just a plastic nipple with a check valve. The connection on the drivers side cover is just a breather that allows air to enter the motor to replace whatever air is removed through the PCV valve.

It will run fine with the PCV valve disconnected and using breathers on the valve cover or better yet running a pair of hoses from the rocker covers to a remote mounted catch can that is vented, like I have on my 93 SC with the turbocharged v8. Downside is the unpleasant smell and small amount of smoke or steam, especially in winter when running the heater because of where the air inlet vents are located.

David

Jacob_Royer
08-30-2013, 02:23 PM
It made me feel better about my build that davec73s Dalke built motor does the same thing.. why?? Still not sure! Matt you got to witness the phenomenon when we were road tunning my car! I'll never forget the alarmed look on you're face when the burnt oil smell hit lol mine ONLY blows by the dipstick tube still debating a "Race Only" catch system off the dipstick tube. Ice' rubber hose and a oil can plus some zip ties.

820
08-30-2013, 03:24 PM
I like the tuna can. that way it could be said (tuned by-chairle the tuner) hehe

David Neibert
08-30-2013, 03:33 PM
It made me feel better about my build that davec73s Dalke built motor does the same thing.. why?? Still not sure! Matt you got to witness the phenomenon when we were road tunning my car! I'll never forget the alarmed look on you're face when the burnt oil smell hit lol mine ONLY blows by the dipstick tube still debating a "Race Only" catch system off the dipstick tube. Ice' rubber hose and a oil can plus some zip ties.

Or just put a rubber vacuum cap and a small hose clamp on the dipstick tube like I do on my turbo car.

http://www.autozone.com/autozone/accessories/Help-3-8-in-black-rubber-vacuum-cap/_/N-25v0?itemIdentifier=439195_0_0_

David

XR7 Dave
08-30-2013, 03:54 PM
Fancy new oil pans have locking dipsticks. ;)

Not sure why you guys have the blowby under boost, but recommend backing off the tune until it stops doing that. If the rings haven't seated and you beat on the thing too much you'll just ruin the rings. Recommend leak down tests when you have a chance. No sense beating things to death.

Jacob_Royer
08-30-2013, 04:34 PM
Fancy new oil pans have locking dipsticks. ;)

Not sure why you guys have the blowby under boost, but recommend backing off the tune until it stops doing that. If the rings haven't seated and you beat on the thing too much you'll just ruin the rings. Recommend leak down tests when you have a chance. No sense beating things to death.

Mine has 5/6k on it now its probably about as broke in as it can get I assume

XR7 Dave
08-30-2013, 04:40 PM
Mine has 5/6k on it now its probably about as broke in as it can get I assume

Well, if's blowing out oil then you have too much timing in it and you are detonating the motor. It won't last forever like that.

davec73
08-30-2013, 07:46 PM
Well, if's blowing out oil then you have too much timing in it and you are detonating the motor. It won't last forever like that.
I have only haad this car above 5000 rpms once myself besides when it was dyno tunned. I re routed the vacuum lines to the oil seperator and re installed the pcv and driver side vac line it the way it was. I will pull timing out of the tune if somone would direct me how much to pull out of it. I have all the data logs from when I have driven the car, I have not driven it hard at all and ocassionnally when it goes into boost it spits a little oil out the dipstick tube and the oil cap, I don't want to give anyone the wrong impression its not that much oil that is coming out but it still bothers me that it is doing it. The car runs better than it ever has, and I have a lot of the bugs worked out of it with the exception of the crank case pressure issue any help on this is greatly appreciated!

Jacob_Royer
08-30-2013, 08:22 PM
Well, if's blowing out oil then you have too much timing in it and you are detonating the motor. It won't last forever like that.

I can pull more timing its only at 21 if I recall

Jacob_Royer
08-30-2013, 08:25 PM
Well, if's blowing out oil then you have too much timing in it and you are detonating the motor. It won't last forever like that.

You know that makes sense because it blows WAY less oil than it did with the stock timing (which was way too much!)

davec73
08-30-2013, 11:32 PM
my max wot timing is set to 17 deg on the no alcohol tune, How much less timing should I run?

XR7 Dave
08-31-2013, 12:07 AM
my max wot timing is set to 17 deg on the no alcohol tune, How much less timing should I run?

That should be fine. But the question is, are you actually at WOT when this is happening? Did you datalog it happening and then look at the timing and AFR that was present at that time?

I'm not trying to make this super complicated or to scare you, but basic diagnostics applies here. You shouldn't be getting excessive blow by. I understand that when we were tuning the car your oil cap was all fubar so I wasn't concerned about what was going on there. Maybe there was something extra going on that we didn't identify? With all the zip ties and voodoo you were doing I just wrote it off as installer error on the oil cap.

If it's pressurizing the case at moderate boost and timing levels, then something is wrong. Maybe you need to do a leak down and compression test. If you do though, make sure you do it right because there in only one thing worse than a bad ring seal - that's thinking you have a bad ring seal and taking it all apart only to find out that you didn't.

Just sayin.

davec73
08-31-2013, 12:40 AM
That should be fine. But the question is, are you actually at WOT when this is happening? Did you datalog it happening and then look at the timing and AFR that was present at that time?

I'm not trying to make this super complicated or to scare you, but basic diagnostics applies here. You shouldn't be getting excessive blow by. I understand that when we were tuning the car your oil cap was all fubar so I wasn't concerned about what was going on there. Maybe there was something extra going on that we didn't identify? With all the zip ties and voodoo you were doing I just wrote it off as installer error on the oil cap.

If it's pressurizing the case at moderate boost and timing levels, then something is wrong. Maybe you need to do a leak down and compression test. If you do though, make sure you do it right because there in only one thing worse than a bad ring seal - that's thinking you have a bad ring seal and taking it all apart only to find out that you didn't.

Just sayin.
No im not at wot I have only cracked it wide open once since I have had the car back here. The oil cap is down tight but it isn't oem so it leaks a bit out of the cap because the threads don't seal good. The dipstick tube has been seeping a little oil out but I found I had a bad hose coming from the bottom of the brake res to the pump motor. With the fueling issues I have had since coming back from the dyno I have babied the car and tried to get steady data logs so the idle and part throttle logs can be read. The problem I found so far was the wideband 02 was loose in the header so I pulled it out and cleaned it with maf cleaner and replaced both of th nb 02 sensors because they were fouled. Today I re serviced the ac and re routed some lines for the pcv and put a zip tie or clamp an every vacuum line I thought it was necessary to do so. I cleaned and remounted the throttle body and moved some other things around to fit better since I moved the oil separator. The car idled very good and didn't smell like it was running nearly as rich at idle but due to the 100 deg heat I decided not to drive it til next week. Next week I plan to drive it locally and take some datalogs as well as put in boost a little to see what if any changes I see in the crank case issue. I also noticed today that my pcv valve was a weird part # so randy has a known good one for an sc that I am going to install as well. I havnt seen any evidence of oil fouling on the plugs the times I have changed them I have only seen excessive carbon build up from the car running rich at idle due to the 02s and spark plg wire on 5 getting burnt by the header. Either way it is coming to the shootout.

Jacob_Royer
08-31-2013, 03:41 AM
Mine only does it on a hard pull at 15psi and isnt nearly as noticeable since matt changed my timing from stock. I've also observed no leaking from the oil cap area OR any oil going out the driver side valve cover vent. Seems of it was really bad blow by that it would be? My dipstick does not snap down like it used to and I'm not really sure of the condition of the o ring.

XR7 Dave
08-31-2013, 09:12 AM
Dave, with all the little things you've had wrong up to now I think we can all agree that pretty much any data or anything you've observed is of questionable validity so I agree with you being cautious, particularly with the overheating and hot weather issues you've had to deal with. I think you have the right idea other than I don't think venting the PCV right now is the answer to the problem.

I do know that if you get your vacuum lines all full of oil they will not work correctly. I had a car one time where someone had hooked vacuum lines up wrong and gotten oil up in all the lines everywhere. Nothing would work right until I took all the lines off and rinsed them out with brake clean and re-assembled. So be aware of oil in the hoses.

As for timing and detonation - WOT timing is only used at WOT. If you aren't going WOT, then it's using the part throttle tables. You could very well be seeing too much timing at part throttle boost which is why you have to datalog and see what is going on there. Part throttle timing is rpm vs. load.

Jacob, 21 deg is still a lot if your heads are mostly stock.

Jacob_Royer
08-31-2013, 09:22 AM
Dave, with all the little things you've had wrong up to now I think we can all agree that pretty much any data or anything you've observed is of questionable validity so I agree with you being cautious, particularly with the overheating and hot weather issues you've had to deal with. I think you have the right idea other than I don't think venting the PCV right now is the answer to the problem.

I do know that if you get your vacuum lines all full of oil they will not work correctly. I had a car one time where someone had hooked vacuum lines up wrong and gotten oil up in all the lines everywhere. Nothing would work right until I took all the lines off and rinsed them out with brake clean and re-assembled. So be aware of oil in the hoses.

As for timing and detonation - WOT timing is only used at WOT. If you aren't going WOT, then it's using the part throttle tables. You could very well be seeing too much timing at part throttle boost which is why you have to datalog and see what is going on there. Part throttle timing is rpm vs. load.

Jacob, 21 deg is still a lot if your heads are mostly stock.

A little cleanup on the ports and that's it on my heads. It can easily be reduced a bit more! I've not heard any spark knock nor have I noticed any spikes in the spark on my logs (did look erratic with the horrible stock values)

XR7 Dave
08-31-2013, 10:26 AM
A little cleanup on the ports and that's it on my heads. It can easily be reduced a bit more! I've not heard any spark knock nor have I noticed any spikes in the spark on my logs (did look erratic with the horrible stock values)

Stock values are not horrible with stock parts. In fact stock timing worked pretty well when the engine was stock. An 89-93 was only making 11-12psi boost and remember, the stock exhaust system. When they improved the blower in 94 the timing was significantly reduced.

Anyway, 18 deg would be "safe" on your motor, and 21 would be considered aggressive since your heads really aren't ported at all.

Jacob_Royer
08-31-2013, 11:01 AM
Stock values are not horrible with stock parts. In fact stock timing worked pretty well when the engine was stock. An 89-93 was only making 11-12psi boost and remember, the stock exhaust system. When they improved the blower in 94 the timing was significantly reduced.

Anyway, 18 deg would be "safe" on your motor, and 21 would be considered aggressive since your heads really aren't ported at all.

So 21 would probably be fine running some race fuel but on 93 cut back to 18?

davec73
08-31-2013, 12:15 PM
Dave, with all the little things you've had wrong up to now I think we can all agree that pretty much any data or anything you've observed is of questionable validity so I agree with you being cautious, particularly with the overheating and hot weather issues you've had to deal with. I think you have the right idea other than I don't think venting the PCV right now is the answer to the problem.

I do know that if you get your vacuum lines all full of oil they will not work correctly. I had a car one time where someone had hooked vacuum lines up wrong and gotten oil up in all the lines everywhere. Nothing would work right until I took all the lines off and rinsed them out with brake clean and re-assembled. So be aware of oil in the hoses.

As for timing and detonation - WOT timing is only used at WOT. If you aren't going WOT, then it's using the part throttle tables. You could very well be seeing too much timing at part throttle boost which is why you have to datalog and see what is going on there. Part throttle timing is rpm vs. load.

Jacob, 21 deg is still a lot if your heads are mostly stock.

I double checked EVERYTHING yesterday and I am also going to smoke test the exhaust and vacuum this week but that is why I started this thread to make sure letting the crank case breath to ambient air wasn't the answer. So moving fwd I am going to check the exhaust and vacuum lines for leaks and fix any that I find, recalibrate the wideband, reset adaptive memory and drive it some next week. After I have have driven it a few times I am going to pull the 02s and plugs back out and look for oil blow off from the dipstick tube and oil cap. If it is still pushing any oil I will perform a leak down test while I have the plugs out but I hope I don't have a ring problem. If I do have a ring problem I wont be racing or dynoing this year but I plan to get to Winchester early Friday possibly Thursday night for the shootout.

davec73
09-14-2013, 06:08 PM
Checked compression Friday and its 150 to 158 across all cylinders so I pulled the plugs and replaced them with xp103 iridium autolites gapped at .035. cleaned the carbon/soot off of the wideband and replaced the narrow band 02s. Smoke tested exhaust and vac lines, no leaks. The oil cap I have in is billet and doesn't seal on the valve cover so I am going to put a stocker on while im driving it and see what I get out of the valve cover. The only issue I have is the car running pig rich at idle. I think a few guys have had this same problem when running long tube headers with a big cam. All in all its pretty close just needs some spit and polish and on the trailer to the shootout it will go!

Jacob_Royer
09-14-2013, 06:31 PM
I dropped my max timing at wot to 18 and put a vacuum port cap and hose clamp on the dipstick tube and I can go 15psi all day long with no oil blowing out !

KMT
09-14-2013, 08:03 PM
I dropped my max timing at wot to 18 and put a vacuum port cap and hose clamp on the dipstick tube and I can go 15psi all day long with no oil blowing out !

What about the car?